Prospectus excerpt:  13,200,000 shares of 61/2% Series D Cumulative Convertible Preferred Shares plus up to an additional 1,980,000 Series D Preferred Shares that we may issue and sell upon the exercise of the underwriters' overallotment option.

Distributions: Investors will be entitled to receive cumulative cash distributions on the Series D Preferred Shares at a rate of 6.50% per year of the $25.00 liquidation preference (equivalent to $1.625 per year per share). Distributions on the Series D Preferred Shares are payable quarterly in arrears on February 15, May 15, August 15 and November 15 of each year, or if not a business day, the next succeeding business day, beginning February 15, 2007. Distributions payable to investors on the Series D Preferred Shares issued in this offering will be cumulative from the date of original issuance.

Liquidation preference: If we liquidate, dissolve or wind up, you will have the right to receive $25.00 per Series D Preferred Share, plus accrued and unpaid distributions (whether or not declared) to the date of payment, before any payments are made to our common shareholders or to holders of any other of our equity securities that we may issue ranking junior to the Series D Preferred Shares as to liquidation rights (but after any payments are made to holders of our debt, holders of our subsidiaries' debt and holders of any other of our equity securities that we may issue ranking senior to the Series D Preferred Shares as to liquidation rights (which equity securities we may authorize only with the affirmative vote of the holders of at least two-thirds of the Series D Preferred Shares)). Your rights to receive the liquidation preference will be subject to the proportionate rights of each other series or class of our equity securities ranking on a parity with the Series D Preferred Shares that we have issued or may issue in the future (including our Series B and Series C preferred shares).

Ranking: The Series D Preferred Shares will rank, with respect to distribution rights and rights upon our liquidation, dissolution or winding up: junior to all of our existing and future debt obligations; senior to our common shares and to any other of our equity securities that by their terms rank junior to the Series D Preferred Shares with respect to distribution rights or payments upon our liquidation, dissolution or winding up;on a parity with our existing Series B and Series C preferred shares and with other series of our preferred shares or other equity securities that we may later authorize and that by their terms are on a parity with the Series D Preferred Shares with respect to distribution rights or payments upon our liquidation, dissolution or winding up; and junior to any equity securities that we may later authorize or issue and that by their terms rank senior to the Series D Preferred Shares (which we may only authorize with the affirmative vote of the holders of at least two-thirds of the Series D Preferred Shares).

Conversion rights: You, at your option, may convert some or all of your outstanding Series D Preferred Shares initially at a conversion rate of 1.9231 common shares per $25.00 liquidation preference, or the Conversion Rate, which is equivalent to an initial conversion price of approximately $13.00 per common share (subject to adjustment in certain events). Except as otherwise provided, our Series D Preferred Shares will only be convertible into our common shares. See "Description of the Series D Preferred SharesùConversion Rights" below.

Company conversion option:On or after November 20, 2011, we may, at our option, convert some or all of the Series D Preferred Shares into that number of common shares that are issuable at the then applicable Conversion Rate, which we refer to as the Company Conversion Option. We may exercise the Company Conversion Option only if the Closing Sale Price (as defined below) of our common shares equals or exceeds the then applicable conversion price of the Series D Preferred Shares for at least 20 Trading Days (as defined below) in a period of 30 consecutive Trading Days (including the last Trading Day of such period) ending on the Trading Day immediately prior to our issuance of a press release announcing our exercise of the Company Conversion Option. See "Description of the Series D Preferred SharesùCompany Conversion Option" below.

Payments of distributions upon conversion:If you exercise your conversion rights, upon delivery of the Series D Preferred Shares for conversion, those Series D Preferred Shares will cease to cumulate distributions as of the conversion date and you will not receive any cash payment representing accrued and unpaid distributions on the Series D Preferred Shares, except in those limited circumstances discussed below. Except as provided below, we will make no payment for accrued and unpaid distributions, whether or not in arrears, on Series D Preferred Shares converted at your election, or for distributions on the common shares issued upon such conversion. If we convert your Series D Preferred Shares pursuant to the Company Conversion Option, whether prior to, on, or after the record date for the current period, all unpaid distributions that are in arrears as of the Company Conversion Option Date will be payable to you. See "Description of the Series D Preferred SharesùPayment of Distributions Upon Conversion" below.

Conversion rate adjustments:The Conversion Rate is subject to adjustment upon the occurrence of certain events, including if we distribute in any fiscal quarter to our common shareholders any cash, including quarterly cash distributions, in excess of $0.21 per common share (subject to adjustment). See "Description of the Series D Preferred SharesùConversion Rate Adjustments" below.

Adjustment to conversion rate upon certain fundamental changes:If you elect to convert your Series D Preferred Shares in connection with a Fundamental Change (as defined below) that occurs on or prior to November 15, 2011, we will increase the Conversion Rate for the Series D Preferred Shares surrendered for conversion by a number of additional shares determined based on our share price at the time of such Fundamental Change. See "Description of the Series D Preferred SharesùThe Increase in the Conversion Rate" below.

Rights upon a fundamental change: In the event of a Fundamental Change, you will have a special right to convert some or all of your Series D Preferred Shares on the Fundamental Change Conversion Date (as defined below) into a number of our common shares per $25.00 liquidation preference equal to such liquidation preference, plus accrued and unpaid distributions to, but not including, the Fundamental Change Conversion Date, divided by 98% of the Market Price (as defined below) of our common shares. In the event that you exercise that special conversion right, we have the right to repurchase for cash all or any part of your Series D Preferred Shares as to which the conversion right was exercised at a repurchase price equal to 100% of the liquidation preference of the Series D Preferred Shares to be repurchased plus accrued and unpaid distributions to, but not including, the Fundamental Change Conversion Date. If we elect to exercise our repurchase right, you will not have the special conversion right described in this paragraph. See "Description of the Series D Preferred SharesùSpecial Conversion Right of Series D Preferred Shares upon a Fundamental Change; Company Repurchase Right" below.

No maturity; redemption:Our Series D Preferred Shares have no maturity date. We are not required to redeem or repurchase the Series D Preferred Shares, and, except as described below under "Description of the Series D Preferred SharesùSpecial Conversion Right of Series D Preferred Shares upon a Fundamental Change; Company Repurchase Right" or "ùRestrictions on Ownership and Transfer", may not elect to redeem or repurchase, the Series D Preferred Shares. On or after November 20, 2011, we have the right, in certain circumstances, to require you to convert your Series D Preferred Shares. See "Description of the Series D Preferred SharesùCompany Conversion Option" below.

Voting rights :Holders of any series of our preferred shares, including the Series D Preferred Shares, generally have no voting rights. However, if we do not pay distributions on our Series D Preferred Shares for six or more quarterly periods (whether or not consecutive), the holders of the Series D Preferred Shares, voting together with the holders of any other series of our preferred shares which have similar voting rights, including our Series B and Series C preferred shares, will be entitled to vote for the election of two additional trustees to serve on our board of trustees until we pay all distributions which we owe on our preferred shares. In addition, the affirmative vote of the holders of at least two-thirds of the Series D Preferred Shares is required for us to authorize, create or increase the number of shares ranking senior to the Series D Preferred Shares or to amend our declaration of trust in a manner that materially and adversely affects the rights of the holders of the Series D Preferred Shares.

Listing:We will file an application to list the Series D Preferred Shares on the NYSE. If the application is approved, trading of the Series D Preferred Shares on the NYSE is expected to begin within 30 days after the date of initial delivery of the Series D Preferred Shares.

Restrictions on ownership and transfer:Our declaration of trust and the articles supplementary establishing the Series D Preferred Shares contain provisions that limit to 9.8% the percentage ownership of our equity in the aggregate and by class or series, including the Series D Preferred Shares or our common shares, by any one person or group of affiliated persons. Our articles supplementary establishing the Series D Preferred Shares allow our board of trustees to waive this ownership limit. We may prevent any proposed transfer of our shares, including the Series D Preferred Shares and common shares, which would jeopardize our status as a REIT. We have the right to purchase or redeem any shares, including the Series D Preferred Shares and common shares, or refuse to transfer or issue shares to a person (including shares issuable upon conversion) whose acquisition of shares would result in ownership in excess of the 9.8% limit. Any transfer of shares that would result in our disqualification as a REIT or in a person's exceeding this ownership limit which is not waived by us is deemed void as of the date of such transfer. We may repurchase or redeem any shares necessary to maintain our REIT status.

Use of proceeds: We estimate that our net proceeds from this offering (assuming no exercise of the underwriters' overallotment option) will be $320.2 million after deducting the underwriting discount and other estimated expenses of the offering payable by us. We presently intend to use the net proceeds from this offering to repay outstanding borrowings under our revolving credit facility and for general business purposes, including acquisitions.

Settlement date: Delivery of the Series D Preferred Shares will be made against payment therefor on or about October 11, 2006.