I'm so glad that someone has finally broken the superhero game curse. Sure you had Super Heroes of Hoboken, which was a good game itslef, but everyone was looking for someone to create a game that would allow you to make your own super heroes and heroines. I'd have probably bought this game even if it'd been universally panned, the fact that its a great game, makes this curse-breaking all the better.
First a couple gripes: the interface is good but sometimes a bit kludgy. Some way of controlling the camera without pressing a keyboard key would have been very nice. Also, without a cheat, you have to wait far too long to recruit your custom superhero. I'm hoping a mod or expansion comes out to allow you to use your custom heroes through an entire campaign (even if it's different). Finally, though I've not tired it, I find it hard to believe that multiplayer is any fun. Without a cooperative mode, I'd have just as soon it was left out all together in favor of more single player missions.
However, there's so much that's good about this game. It's a nice mix of a tactical combat game with some RPG elements thrown in. The premade heroes are excellent especially when you throw in the little animated secret origin clips. I'd have loved for the campaign to go on for a few more missions if only to allow more character exposition. While the XP and prestige system seems chinsy at first, it's definitely well balanced and works to foster some replay. How else are you going to answer questions like, could I beat that mission better with El Diablo instead of the Ant, or should I get Minute Man's Patriot Whirl before I beef up his Eternal Vigilance?
Another high point is how the game captures that comic book feel in every way, right down to the little comic covers that appear in the installation program as well as the load screens. I know some have found the announcer guy annoying, but I love it and am even working on my own imitations. Sight, sound effects, and voice acting all work together to make this feel like a comic book where you control all the action.
Definitely something to buy if you have any love of comic books or superheroes in general. Also something to buy if you're looking for a nice light tactical game.