My 5 minutes on Ubuntu 11.04...

• New UI looks nice (but I prefer the old one)
• New style scrollbar makes me confuse a bit (but it's one of the good thing that I like)
• Apps menu appear on top panel instead of on its own window (except for Libre Office apps)
• Quick search for apps (very helpful if you know the name)
• Unable to customize panel
• Enabling desktop cube via ccsm will cause top panel and app launcher stop responding. Windows border disappear
• Overall, I don't like it. I'm glad that I switched to LM last year.