I've been running 10.04 LTS (Lucid Lynx) beta1 for a while now in my VirtualBox environment. So far it seemed pretty slick but I haven't had much chance to play with it. One thing that stood out though was the MeMenu. I call it 'the push here for social networking button'. Me like. Twitter, facebook, flicker plus a few others all bundled into one app - Gwibber. Not sure about the name though.
I'm really excited about this single feature because this is the number one task that I do on my Ubuntu Netbook remix Dell Mini 10v. Right now I use Tweetdeck's Adobe AIR version. While it's functional it does have several issues. Needless to say as soon as the network traffic frenzy typical for a new release dies down, I'll update my netbook.
As far as the virtualbox version goes - I updated to the latest RC (release candidate). Immediately my X-server crumbled prompting me for several options to redeem itself. None seemed to work. Not sure if this was as a direct result of the VirtualBox additions or not. Whatever - I'll get to it after I update my UNR Lucid Lynx - my SNOS machine!