Not very long, and not worth a second playthrough.
One time when I was younger I read two books - Jurassic Park by Michael Crichton and Jurassic Park: The Junior Novelization by Gail Herman. One book was full of detail - in-depth, graphic and involving, Crichton's Jurassic Park quickly became one of my favourite books ever. The other jumped from plot point to plot point, obviously focused on delivering just the core details.
Xmen Origins: Wolverine is the Crichton Jurassic Park to the film's Junior Novelization. It's very graphic, it goes into plot points not even considered by the movie and I found myself struggling to put it down. The game does Wolverine justice - something the film fails at miserably.
The game and film are so different however that I won't mention the film again. Certainly you'll recognise lines similar in both, and the story has the same general idea but they're still very, very different. So the film doesn't exist. Xmen Origins: Wolverine is your real Xmen Movie Universe canon.
Xmen Origins: Wolverine is the first game where I was able to backhand a person's head off their shoulders. In my books pouncing across an area and landing claws first on a dude, stabbing him five or six times and then backhanding his mate's head off is worth serious points. Chopping off both a dudes arms is worth a bit too.
In fact, there are quite a few "**** YEAH!" moments in Xmen Origins: Wolverine. The first time Logan's body is ripped to shreds by gunfire and you can see his organs working inside his rib cage is something you just won't see anywhere else. Starting the game sees you leap from a Helicopter and squish a dude. You can tear a monsters head off.
A lot of the "**** YEAH!" stuff comes from the type of game it is - Xmen Origins: Wolverine is an unashamed God of War clone. Sure there hasn't been a cut-scene where you can see through a hole in Kratos's chest - but there aren't any boobies in Wolverine's game. Both game's feature faux RPG style skill systems and rage bars - in fact the one thing Wolverine is missing from the God of War series is the combo meter. Sometimes you want to see on the screen just how many soldiers you've ripped to shreds.
If you've played the God of War series you already know the basics - you have light and heavy attacks, special attacks and a block button you'll rarely ever press. The pouncing system - wherein you crouch down and leap across the level - is a new and added bonus, even making it's way into some puzzles in the game. It's strange that Logan can't leap unless there's a person to leap onto, but I guess it fits with the violent nature of the beast.
Speaking of puzzles, the game has an almost Tomb Raider vibe with some of its puzzles - moving blocks to uncover platforms and dodging spike traps had me almost expecting a T-Rex to come tearing out of the jungle. On the levels not set in the jungles of Africa the puzzles tend to involve carrying an oversized key somewhere for whatever reason.
The level design is typically intuitive, and our hero further helps things along with his "feral senses" (apparently "spidey senses" was both taken and not particularly appropriate). By tapping up on the dpad the world will turn grey, highlighting objectives, enemies and junk you can smash. Funnily enough the only times I felt I really needed to use the senses was when the plot had somehow stripped me of them - decidedly inconvenient.
The faux RPG style skill system I mentioned earlier comes into play with the Rage and Health bars - both can be increased (Rage bars allow Wolvie to do super special attacks) - as well as increase the power in his attacks and special moves. It doesn't come into play
immediately - the game eases you into everything at the very beginning. The RPG system doesn't really make or break whether you can defeat enemies - you work out their weakness and you exploit it - so you won't have to go around smashing boxes (smashing junk is worth xp!) just to be prepared for a boss.
I'm extremely impressed with Xmen Origins: Wolverine. It's a solid action title, it delivers fantastic special effects and the game flows with ease. It lacks a little in the replayability department - some kind of scoring system might have been a good way to encourage people to play through again - and the story jumps around a bit, which might prove confusing to some. The regeneration effect is something other games would do well to "appropriate" for their own use, and the graphic violence is at the perfect level for Weapon X - but I don't know if I'd purchase Xmen Origins: Wolverine.
The best reason to buy this is if you don't think you can hold out until God of War 3 - the other reason is if you're a huge fan of the character. You'll find that this is ultimately the definitive version of the Xmen Origins story.