Perhaps the majority of movie critics went into Hancock expecting a superhero movie, and who could blame them? It's a movie about a superhero. But after a single viewing it should become apparent that the film has nothing to do with superheros saving the helpless masses from supervillains.
In fact, the villains in the movie exist only to affirm Hancock as a crime-fighting vigilante. They're not only secondary to the main story line, they're practically background props. The true challenge to Hancock isn't any bad man - Hancock's obstacle is himself (which shouldn't suprise anyone considering that the movie was pitched as being about a drunken, ill-tempered superhero).
I'll agree that the movie's action sequences could've been more glorious and better planned out, but once again, this movie's not about that. Perhaps to really 'get' what Hancock is about, imagine that he wasn't a superhuman nor a hero. Pretend that Hancock was just a troubled guy with loads of potential to do good in the world. Because the superhero aspect is just this story's way of reinventing the troubled individual. A juxtaposition, if you will.
I really enjoyed this movie, so I'm giving it 8/10. It's highlights are an interesting story and enjoyable actors playing their roles. It's low-points are that it tries to be funny, action-packed, and story-telling all at the same time so its efforts aren't focused enough. Perhaps if they dropped the special-effects action sequences and focused on the characters it would be a great movie (though not a summer blockbuster). Or they could've just ditched the story and cast another big name as the role of a supervillain and the critics would eat it up. (I'm referring to you, Ironman.)
Final note: I'm craving spaghetti and meatballs.