I enjoyed the movie, but there was some sillyness in it. I didn't like Professor X at all in it, I don't get how he blamed Wolverine for Jean/Phoenix waking up. He didn't do much besides warn, whine, and die. And then come back to life.
The lines and dialog was largely crap. I never liked Cyclops anyways so I don't mind his death that much. Wolverine was too weepy all the time though. I don't like Jean getting 'cured', I do like how Wolverine didn't talk her out of it, just made her think about it.
I thought the deaths were good in the movie, and besides that I liked the action sequences, basically. I was waiting for Magneto to start using the cars as ballistic weapons, that's always fun. It was a great big mutant party.
I haven't read many of the comics (though I have seen the cartoons!), but I was hoping Magneto would be less evil, not sure if that fits. One thing I like about this series is how the bad guy is completely right in his own mind and isn't too evil about it. As well as how mourned Charles' death.
Like the hobo said, if they make money off of this, they may make more, and it is probably decent as far as summer movies go if you're looking for some fun. But if you've read the comics, you'll probably be less inclined to agree with me.