You're right, it's not available outside of the US yet.It's roughly the same reason why the available songs/movies/television shows/applications in the iTunes Store aren't the same in every country. The US has the most Mac users, we didn't want to wait until we got the other countries lined up to get the trial out there.
Regards,
Nadyne.
Nadyne, your input on Office for Mac is much appreciated, but the rationale for the restriction of the trial to US users for now is a bit thin. There are more than a few Mac users outside the States, who would appreciate a 30 day trial (though IIRC, the trial version of Office 2007 is for 90 days - is this to punish Mac users, or are they considered better able to assess the product quickly?).
Come on, get your colleagues to let the rest of us try it out!