The Avengers. It's what we call ourselves, sort of like a team. "Earth's Mighiest Heroes" type thing.
-Tony Stark

Thought I would like it less the second time around and I was wrong. I was actually able to appreciate it more without having my mind all buzzed out on the hype this time.

First off Joss Whedon was the perfect director for this film and his screenplay is fantastic. The dialogue itself is entertaining from beginning to end. Anyone familiar with Whedon would suspect his handy work without looking at the credits. He understands these characters and everything they say and do is true to form. That on it's own is something rare for summer blockbuster movies, zero characterization is usually the norm. It also accomplishes something that none of the X-Men films were ever able to do and that's make a true team movie where each character actually feels important and not just one or two (I'm looking at you Wolverine).

This being a direct sequel to four different movies the story manages to actually grab elements, not just characters, from all four films and make them relevant. You probably don't need to watch all five movies that came before (Iron Man has a sequel of it's own) to enjoy The Avengers but it does add tons to the overall experience.

The action and special effects are top notch. I'm thankful it took this long for an Avengers film to be made because the CGI is actually able to pull off what they want to do in the film. Scenes that I know logically have to be CG don't look sterile, actors standing in what has to be "green screen rooms" don't seem out of place and The Hulk has never looked this good before.

In comic books every so often they have these huge crossover events where the storylines from different solo comic books come together in one huge mini-series (Ex: Infinity Gauntlet, Civil War, ect). These stories are usually "game changers" and effect the heroes in different ways for future stories. Marvel Studios has taken this concept into movies and they've pulled it off. The Avengers captures this huge event feeling to perfection.

Last thing: The best depiction of The Hulk outside of comic books period.