Oh, and beware: Here Be Spoliers.
Being slightly slower off the mark than usual, I made it to Spidey 2 last night. If you saw the first one, then you'll have a pretty good idea of what to expect, although I'm certainly not saying that's all bad - if it ain't broke, etc.
The similarities in plot and action are many and obvious: to be a superhero or not, burning buildings, conflicted villains, and would you please just sort it out with MJ?
Actually, it's the character stuff that makes the film. The action sequences show off just how good CGI is getting (compare the Matrix sequels' disappointing 'virtual actors' with a couple in here that are much more like it - you can still tell, but that just means you can be impressed :-), but they are overshadowed by Peter Parker's convincing inner turmoil, and especially by Alfred Molina's bad guy.
Doc Ock is a brilliantly sympathetic character, pulling you along as the good man weakened by his ambition, and you'll be glad of the little bit of redemption he's allowed at the end.
It does take a little while to get past the similarities with the first film, but the rest is much stronger. We're also set up for what could be a much more satisfying third installment, since a certain tension that has been going on for a distracting two whole movies is finally released