Thats good to hear, exploder. I'll give it a shot also.
I prefer KDE to Gnome, but dumped KDE until it could be brought stable. So now I'm used to Gnome again. My experience with Kubuntu-vs-Ubuntu is that Kubuntu was sluggish and slow by comparison, but Mint KDE (Daryna) was as fast or better than the Gnome version. So I chalked that up to Kubuntu not KDE.
The same "old workhorse" laptop currently running Jaunty-64 has a spare test partition sitting unused right now (last used for Daryna KDE, still functional but hasn't been touched for many months).
I have, thus far, plenty of good to say about Jaunty. I look forward to echoing that sentiment with K-aunty.
As for fullscreen flash and Hulu, it occurs to me that the switch to Xorg 1.6 and the resultant driver changes that imposed on a lot of people, combined with the fact that in Jaunty you're stuck with flash-nonfree instead of adobe-flash packages (the adobe version working much better), might not be the problem. I know for my "old workhorse", Jaunty means no suspend and no hibernate, because I'm stuck with radeonfb instead of fglrx for video. I've lost ACPI support, and my openGL support is down the tubes compared with fglrx. Hulu is choppy both windowed and fullscreen, but fullscreen makes it much more obvious. I pretty much can't stand to watch anything on Hulu other than cartoons, which is all I usually watch on Hulu anyways, but I also notice similar choppiness with Youtube (esp HD, esp fullscreen). Bandwidth (and buffering) are obviously additional factors. But I'm left with the conclusion that the problem is solvable and that the solution is probably in the pipeline already and will likely appear on or before the end of this month with Jaunty's full release.