It's mixed for me.
The trackpad sometimes gets really hard to use if your hands are a little moist. <snip>
Yabut� with the trackball, that moisture is transferred with the trackball rotation into the inner workings and hidden mechanisms of you BlackBerry, waiting to wreak untold havoc! :-) Trackpad FTW IMO.
Posted from my CrackBerry at wapforums.crackberry.com
I have a 9700 and a 9800 and I have never seen an issue with a trackpad on a 9700 or 9800, BUT most of my friends with Curve 8520/30's have massive trackpad issues.
The trackpad is soo much better than a trackball. I remember with my 8330 curve, the ball would give me trouble sometimes with the scrolling but now with my 9700, I have had no problems with it.
I like the trackpad but i never had a problem with any of the phones with trackballs in the tour or curve... i think the trackball was easier to use and i know a lot of people who are now having problems with the sensors on their trackpads .... theres always going to be some problem lol!
I've had my 9700 for a little over a year & not noticed any problems with the trackpad. Given, it does lean slightly, but not noticeable, doesn't cause any problems with usage.