Disclaimer: I am a comic book collector so my review is slightly biased by proxy. But bear with me for a moment.

The Avengers comics are some of my favorite Marvel comics (besides the "New Avengers" and the "House of M" comics) but the movie didn't live up to the legacy of the comics. The jokes in the movie were really good I gotta give them that. But humor alone isn't a good foundation for a movie (unless we're talking about movies which pertain to the Comedy genre, which is clearly not the case here)

The biggest problem that I personally had with the movie was the fact that 50% of the action in the movie happens on what appears to be a spaceship, that is reminiscent to those of the Start Trek franchise (I mean, an invisibility cloak? Come on now. Is this a joke? Because I'm pretty certain that the Avengers Quinjet didn't have this feature in the comics, /last time I checked, anyway)

In my opinion they should have simply titled the movie "Attack of the spaceships". Because that's the only consistent theme in the movie: spaceships.

Also, all of the main protagonists acted like little children throughout the majority of the movie. And then at the end they miraculously got a hold of themselves... *movie logic* Furthermore the HULK's development was completely unrealistic. At first he is this uncontrollable mess that can't be reasoned with. But then at the end he has absolute control over his alter ego ... *movie logic* (such a learning curve is unrealistic to say the least)

On a side note: the new Captain America suit looks goofy. What were the costume designers thinking? A helmet? ... Remove the helmet and give him his protruding wings on his headpiece back. For the love of God.

Instead of aimlessly pumping out movie adaptations Marvel should take it slowly and try to focus more on the quality of their movies (Quality > Quantity)

p.s. I'm not even going to rant about the fact that Marvel had to introduce yet another Universe just to make the movies work (because they are a-canon by nature ergo non-compliant with the original Marvel canon and the respective origin stories of the Avengers).

p.s.s. the reason why I'm so passionate about these types of movies (comic book adaptations) is because most people don't really care about the franchise. For them some fight scenes and explosions are completely sufficient. Not for me, thought. I genuinely care about the franchise and would like to see movies that do the genre justice. After all, people like me (Nerds) were the ones who made the comics a success to begin with. Long before there were any blockbuster movies about super heroes.