After installing Xubuntu x64 on my computer with Core 2 6700 w/ 8GB RAM, I have these issues.
(1) Video playback is choppy (ATI 4850 w/ 1GB RAM card)
(2) No sound (Creative Xi-Fi Extreme Gamer card)
This is after letting Xubuntu update itself using the Software Update center.
I am not a Linux guy, but if these basic things don't work, I am not going to bother using it.
Fedora 13 is going to be released under 2 weeks. I'm going to try it out too.