I've had this exact same problem. RIM is a client of mine, and a guy in their engineering department acknowledged this exact behavior is a known issue and will be addressed in the next generation of products. I went through 4 replacements from Verizon until I made them give me my money back (but they oddly enough didn't make me send the phone back).
I have tried replacing the trackball, then noticed it is the little "spring" switch on the circuit board that is the problem. I can barely touch it with a pen or similar and it will fire the "click" action, whereas this behavior should only happen if you press hard enough to actually "spring" or "click" it.
Call me pessimistic, but it seems like with the introduction of the 8800/Curve/Pearl line,
RIM/Blackberry is going after the mass-market consumer and is leaving us demanding, addicted business users behind. I went back to my 8703, which has been dropped, ran over with my bike, and dropped in a puddle of water, yet still works flawlessly. Maybe in 5 years Ixxx8217;ll be that guy carrying around the xxx8220;really old phonexxx8221; (like my father was in 2001, still carrying the Motorola xxx8220;Tote (bag) Phone.xxx8221;