I didn't expect this from the trailer, but Iron Man turned out to be the best superhero movie I've seen since Batman Begins. Beside it just being a well-made action movie with Robert Downey, Jr., I appreciated not knowing anything about the character before entering the theater. I also realized during the film that I prefer superhero movies which don't rely on "magical powers," like Superman, the X-men, and Spiderman all do. I recognize that those films attempt to make scientific explanations, but it's much easier for me to get invested in a character like Batman or Iron Man who underneath the costume is just a regular human. Sure, both Batman and Iron Man have unrealistic strength and engineering abilities, but it crosses the movie-plausibility threshold for me.

See my posts on The Illusionist vs. The Prestige for a similar distinction.