I think the Avengers made money because it was the movie that had been teased since the end of Iron Man, which was also quite successful. I think it was good because of Whedon.
Quite right. It makes no sense to attribute the movie's success solely to the advance hype and the preceding films. Those things created high expectations
for the movie, but if it hadn't actually been good enough to match or exceed those expectations, then the result would've been extreme disappointment and fan outrage. Remember how fans reacted to Spider-Man 3
and X-Men: The Last Stand
-- which weren't really bad films per se, but were significant steps down from their extremely well-received antecedents, and so they fared poorly. So advance hype alone isn't enough to guarantee success. Just the opposite -- it makes success harder, because there's a higher bar to clear. The Avengers
faced as high a bar of expectations as has ever been set for a superhero movie to date (not counting The Dark Knight Rises
, which isn't out yet as of this writing), and it cleared that bar easily. So hell yes, it succeeded because it's a good movie in its own right, and that's largely because of Joss Whedon.