I've been running the beta for months. It's pretty good. Very resource hungry though. Outlook also crashes on exit every fucking time, generating a spew of error logs. Sort of annoying. Overall though it's a very nice, much needed facelift to Office. I have to say the new Excel tabs confuse me a little though. It's intuitive, but you're so used to the old menu system you get confused trying to find what you're looking for.