Mine's OK. It wiped out my config for downloading hotmail in evolution...gaim is gone, but pidgin is the same, my nvida driver isn't working to well, need to play with that.
If anything my wireless is less temperamental than before.
It did have real problems with my screen resolution. It came back at 800*600, and when I jacked it it it screwed up. I reconfigured xserver and now it's fine.
Not issue free, but no more troublesome than upgrading windows