I've been running lucid for a few days, and I think quality control has significantly slipped in Ubuntu. Yes they are only betas, but with only 2 weeks left before release, I have seen lots of bugs still remaining. Within a couple days I found that screen-saver crashes often, several apps can't properly auto-disable PulseAudio anymore and don't work without hacks, PHP 5.3.2 segfaults, themes didn't install fully on upgrade, and (of course) the memory leak which results in Lucid using up all the RAM in my system (yes I've submitted bugs (or found previously submitted tickets) on most of these already). Other things like Wine segfaults seem to be resolved by reinstalling, but overall this upgrade has not gone smoothly for me. I've been, overall, happy with (X)Ubuntu over the years, and like the 6 month cadence, but, in my opinion, they should really focus more on quality for their LTS release. I certainly wouldn't recommend an upgrade to 10.04 in its current state, though I plan to stick with Ubuntu personally. Generally, I consider Ubuntu to be a more user-friendly and more current Debian, which I like, but I guess I should learn not to be an early adopter if I care about stability.