One of my favorite things about this movie is that it doesn't take itself too seriously. Even the most serious villain (Ronan (played by Lee Pace!)...and I guess Thanos, although we don't really see him much) seems over-the-top, exactly like comic book villains are. That was fun. I also really like Chris Pratt's acting. He is cool, but not overly Tony-Stark cool. He is also goofy, and that is entertaining.
I particularly like this poster because there is something very Star Wars-esque about it.