Theres nothing that screams out to me from 2007 to 2010 but some of the outlook features are pretty handy.
The feature where opening a read only file has a simple prompt at the top saying woul dyou like to edit this click yes and you can was pretty cool
no more fiddling about with user rights and properties of the document.
havent tested on a passworded file however.
I use it rarely just got it as a beta tester but ill prob to stick to my openoffice.org system as it does everything and is free.
I read that the 2010 has 3 user licenses in it so 1 copy per 3 machines is pretty good but it might be just on the beta.
There are a few bug where it crashes but thats expected and will hopefully be ironed out in final release.
Tested with windows 7, home office, ultimate and ultimate signature edition. (few more features for those lucky to get a copy was free too lol)
Al