Just got back from Chronicle, and it was pretty much fantastic. DarthTom, you really did yourself a disservice by not sticking around for the last 20-30 minutes, because their intensity and excitement more than make up for the more relaxed pace of the first half. There are some moments there of a type we've seen in action/superhero movies before, but that felt so much more intense here because of the documentary/near-first-person perspective really putting you in the moment. And to some extent it ultimately does become a hero/villain origin story, but it really takes the time to establish how and why these characters go from ordinary teens with banal concerns and limited imaginations to what they ultimately become.
More importantly, of course, the character drama is quite potent and effective. I don't understand how anyone could get the impression that this was meant to be an ordinary superhero film. I mean, it's an indie film for starters, not a studio blockbuster. It shouldn't be hard to figure out that it's taking a different approach to the concept. Essentially it's using the idea of superpowers (along with the idea of a verite/found-footage format) to tell a story about coming of age, the cycle of abuse, and the like. Maybe it's a metaphor for adolescence and maturity, how we discover new abilities and opportunities and have to figure out how to deal with them, with the difference between "heroes" and "villains" being whether we learn from our inevitable mistakes or just keep on making them and become trapped within them.