Jack Black was an integral part of the movie and definitley added a lot to it, but I think Cusak played the role as well as it could have been played. Everyone has gone through the situation he is dealing with and we never realize just how whiny we are at that point....and thats what makes it great. It points out that no matter what life moves on and things get better even when you think it never will.

I dunno it just kinda speaks to me, plus the soundtrack really appeals to my music snob tastes.