It was pretty good. In some ways, I like it more than Marvel: Ultimate Alliance. The graphics were standout and I'm a real fan of the voice acting. They did a good job in translating the various character powers, although there are a few instances that are lacking. The roster is decent for a first time game once you unlock everything, but the repetition concerning the Green Lanterns was a letdown. The plot is executed well, even if its a bit predictable and at times, I marveled at the animation detail.
The main drawbacks were that it was kinda short, you don't have complete control in character selection at all times and some of the villains aren't really that inspiring. I found it a worthwhile purchase and much better than I anticipated. I really got into the leveling up and building stronger heroes, so the replay value was high for me. As a matter of fact, being active in this thread today is probably going to have me fire up a game before the night is over.