X-Men, Next Generation is an interesting bit of work, and a hard game to review: judged purely as a fighting game, it's merely serviceable, not really holding it's own against the other titles on the market. But when judged as a licensed game, it fares better, and those angered with the treatment the children of the atom have received from the gaming industry should not pass this one up.
While the game's graphics leave a bit to be desired, the presentation does adhere to the comic book audience, and the story mode actually has something resembling a story, rather than just a CG movie at the end of a bunch of random battles. As to modes, this isn't VF4, but the casual fighter fan who doesn't absolutely need a kumite or tag mode will find themselves satisfied.
But, you ask, how does it play? Well, that's the thing: while you do have a special meter, and it's not as shallow as say, Kabuki Warriors, those looking primarily for a deep and engaging fighting game would be better off going with Tekken, VF4, or even DOA3. But X-Men fans who are also fans of the genre should be pleased with the progress the license has made since the atrocious Mutant Academy.
-George