When looking for a bike I looked at Trek and Specialized, among others. The Trek was competition till the very end. Parts were comparable, as was cost. I eventually sided with Specialized because it "felt" a bit more suited to me, as well as a more "solid" feel to it.

That aside, I know MANY people on Trek MTB, and they are all happy with them. The important thing is how it feels to you, not what others b*tch about.