I'm very impressed by the new desktop. It's much cleaner than 3.5 - and this with nearly no configuration work. That's a big advantage over kde3 and windows because I and a lot of people who only want to work with the desktop just don't have the time or are to lazy to spend a day or two to configure the desktop for their needs. Especially when you use kde at work.
But I also have three annoying bugs - don't know if they're already in b.k.o.
The first one is that my trashcan don't like me and goes away on every login. The I've massive redraw problems since I updated kde this morning (it worked much better yesterday). Looks like the digital clock is the problem - I can only reproduce it once the clock gets away on a redraw:
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And the last one (which is maybe related to the redraw problem) - the screensaver screws up my desktop. The only solution is to kill my x server.