I've had my fps be really bad and really good. I've read restarting your PC can do wonders for this game. If that doesn't work try changing a few settings and then rebooting again. It is buggy, that's for sure.
Thats what i did. As soon as i D/L the beta, installed it then tried to play it - it keeps giving me a connection error.
Closed everything down, restarted and i havent had any problems since (except when the server is full).
So far, with my resolution (1920 x 1080, X-Fire enabled):
- Ultra - avg around 45 - 50 fps according to fraps
- High - avg around 65-70 fps according to fraps