X-Men: The Last Stand falls somewhere between the plodding exposition of the first X-Men and the compelling, character-driven X2. In other words, its action-packed but lacks that certain mutant angst.
At best, the horror/thriller genre has been tenuous of late, but Cry Wolf's teenage babble, with its cheap almost-thrills, further skews the line. If you see it, don't say you weren't warned.