As a film, I liked it. It had drama, Eric Dane, cool effects, Eric Dane, a fun premise, and hot guys in black leather (Eric Dane). It delivered some surprises (like the double-whammy deaths of Scott and Xavier). I loved having the five original X-Men in the same movie.
As a comic movie, I share the same gripes as most of you. I know they handled the Phoenix story the way they did, because having her go off into space, introducing the alien species, and letting her destroy planets was....well, it looks good in comics, but is very difficult to accomplish in a movie.
My biggest peeve, though, was reducing Wolverine to a "romance hero" role. Pining after Jean, not giving up on Jean even after she's killed people, and then the whole "Not for them, for you" thing at the end... *cringe* Maybe I just like my unresolved sexual tension, but I much prefer the flirty nature of the Jean/Logan we met in the first two movies.