I don't know if there's an inherent problem with the MacBook track pads, but I think it's worth noting two things.
Firstly, every laptop I have ever seen on display has had a bad track pad. The nature of display machines and the susceptibility of track pads is not a good mix. This seems pretty universal, Mac and PC.
Secondly, going from a track pad on one machine to a track pad on another machine can be very disconcerting. They all have their idiosyncrasies and their different levels of sensitivity. I find it really difficult going from my iBook to my friend's Dell (and vice versa) simply because I'm used to the iBook, not the Dell. If you're coming from a different type of machine, then maybe you're just used to that machine and the MacBook will feel weird until you get used to it (shouldn't take long in the scheme of things). 🙂