2011 is a pain in the neck. It doesn't display documents accurately (especially PowerPoint). I've been dragged in front of my CEO several times because the PowerPoint he is supposed to give is unusable. It always comes back to the fact that it is perfectly formatted in Office 2010 on my PC, but Office 2011 messes it up on his MacBook.
The worst though is Outlook. I'm always being asked how to do something in Outlook, only to say it isn't possible on the Mac, my boss then tearing me down a strip, because he has been doing that for years (yeah, but not on a Mac!). So I am hoping the Outlook update closes the gap and makes more reliable and closer to the functionality under Windows.