Here's a screenshot of Outlook 2010. It's simple and been edited to protect the identity of the end-user as this has been leaked out, it's not an official release.
I like the look of the cleaner interface and the new ribbon, including a Quick Steps menu - common forward tasks to Team, Manager, FYI. You can see the Ignore button too.
There's a peek of the new Office logo as well - I expect an outburst of logos and colour schemes based on this new orange over the next year!