Those who run Xorg and game may be aware of outstanding bugs in xorg-server causing keyboard input drop and wrong or repeated events on mouse input (especially mouse wheel). I tried one patch after another, for three days, and finally gave up and reinstalled an older and less bug-ridden xorg-server. So it's as happy as it's ever been. Other OpenGL games - UT04, Sauberbraten - seem perfectly fine.
But I think I've uncovered a bit of a problem. It does appear mwheelup / down events for weapon switching still causes some very odd behavior. Load up as big a map as you can w/out trouble, spawn a few bots, grab a few weapons and start cycling through them with a mousewheel bind (it's most obvious while turning or moving fast) and you'll see what I'm talking about (yeah...I prolly should throw up a demo). I'll try reproducing this on Windows later tonight. I really don't know what to make of it.