A couple gripes:
Occasional hard locks make me reboot
Every time I log in to KDE4, there is another “Pulseaudio Applet” in my taskbar. It got so bad I had about 9. WTF?
When I log back into KDE4, Firefox will start up if I had it running last time I logged out. Fine, but Flash doesn’t work for some odd reason. I have to restart Firefox to make it work. Gay.
Crossover Games works…most of the time. I’ve tinkered enough to get Civ4 playable, but depending on which way the wind blows, it either plays flawlessly, crashes after 15 minutes, or doesn’t start at all. Gotta love the lack of predictability.
I’m sure there are more, but I can’t remember them at the moment.