The message exceeds 1440 pixels wide in Outlook 2007 and has the right side bar intact but without shading. If the message fit the window better in Outlook 2007, it would be usable.
Outlook 2007 - screen resolution 1440x1050
Outlook 2003 - screen resolution 1280x1024
OWA (Exchange 2007 & IE7) renders the same as Outlook 2003, once you enable blocked content. The Outlook 2007 version looks fine if you use Other Actions, View in Browser menu to open it in IE.
Outlook 2007 isn't the only client that "breaks" html - the following is a message I received in my GMail account and forwarded to Outlook 2003. Keep in mind that forwarding screws up the links by adding 'blocked::', so the images won't download. But you get an idea of how the page was probably supposed to be laid out.
Mail sent to Gmail account, viewed in IE7
Forwarded to Outlook 2003, viewed in internet zone.
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