I've been using the latest beta of Ubuntu 7.04 which is set to be the next major release on thursday. I downloaded the default Ubuntu, as I wasn't sure of the quality of Kubuntu yet. I have to say, I'm very impressed. Hardware support is getting even better, and the new restricted drivers manager makes it a doddle to install proprietary nvidia drivers. When I mean easy, I mean easy. And the thing is, it worked! I started with a 6.10 installation, and did a distribution upgrade as per the wiki and after 600mb was downloaded I had the new release beta. Overall, the quality is high. Wireless support is better than before. I've not tried 3D desktop yet, since I've been running a 15GB torrent over the last few days. I have not shut down the computer once during the many days, and it's been rock solid stable. So far so good .
I've been testing Kubuntu and Xubuntu Feisty Fawn through VMware, and I am very impressed, especially with Xubuntu. I'll actually be replacing Kubuntu Dapper Drake with Feisty this weekend on my main computer, and Xubuntu Edgy Eft with Feisty on my laptop! Can't wait