Short version -- this is one of the most delightfully silly, weird date movies I've ever seen. I mean, when you really dig into it, this is a relationship flick. Scott, our hero, is a somewhat nebbishy guy living in Toronto, who meets the girl of his dreams and wants to win her over. The problem is, in order to date her, he has to defeat her Seven Evil Exes.
Y'see, this movie takes place in the world of video games. Kinda. Sometimes it looks and feels entirely normal, but game logic is utterly pervasive: when you meet one of your girlfriend's ex-boyfriends, of *course* you have to fight. And the fights are no-holds-barred extravaganzas of deliberately ridiculous special effects. Scott may be a nebbish, but he's a great gamer; therefore, it is entirely reasonable that he can mostly hold his own adequately against, eg, the square-jawed Arnie clone. (Although the later boss fights, appropriately, require him to out-think the bad guys, not just out-punch them.)
Helpfully, the movie at no point takes itself too seriously, but at the same time it never explains nor apologizes for its premise -- the rules of this world are simply what they are, and you have to accept them on their own terms. And I don't just mean the fight scenes: the movie tends to go into pure dream-logic from time to time, in a rather videogame cut-scene kind of way. The movie *is* riddled with in-jokes, many of which went over my head, but if you are willing to just go with the flow it's a good deal of fun anyway.
It's based on the graphic novel series of the same name; shockingly, I haven't read it yet. I gather from hungrytiger that the comic is *far* deeper -- unsurprising, given that it's something like 1000 pages all told. The movie chops that down mercilessly, and loses lots of detail. But it stands well on its own, and I gather that it sticks reasonably well to the flavor and high story of the original, even if it has to diverge widely on the details. (That's usually the way any good comic-book adaptation must work.) There's one plot twist that is ridiculously telegraphed in the movie, which I gather works a lot better in the longer form (where the payoff doesn't come 20 minutes after the setup), but other than that I didn't see any serious problems.
Definitely not deathless art -- don't go in with inflated expectations. But it's quite a lot of fun in a terribly geeky way. Frankly, it's one of the best Marathon Movies I've seen in a long time -- I hope they're thinking about picking it up for next year.
(Oh, a side-note lesson about those free passes, if you ever find yourself with one: they give you the right to get in for free, but they are *not* tickets. They appear to have issued about twice as many passes as there were seats, and a lot of people in line didn't get in. We only just barely made it in under the wire ourselves, since I was delayed getting into the city. Moral of the story: if you get one, be prepared to show up *really* early, especially if you don't want to be craning your neck in the front row the way we did...)