That's why I've made a precision: "this violence doesn't quite fit with Wolverine imo, or at least the way Wolverine is shown in the movies."
I don't know the X-Men comics very well, but that's not the point here, this game is based in the X-Men movies universe.
I just found that weird to have a PG-13 movie and then make a M game with ultra-gory violence.

Hmmm... I find it hard to describe my feelings. There IS a point at which the violence stops being cartoonish/bearable and starts being disgusting or disturbing, but it's hard for me to describe where that point is.
Possible signs that a game has gone over the line:
1. Realistic "squishing" sound effects.
2. Visible bones/organs.
3. Red on white backgrounds.
Based on the above standards, Half-Life 2 is pushing against the barrier, but hasn't passed through. I don't think I've played a game yet that was really TOO violent...

The game isn't really based on the X-men trilogy though. it's loosely based on the most recent movie, which showed more of the brutality Wolverine is known for. Though to keep the PG rating, they wimped it up a fair bit.

the 'gore level' must fit the game.
If playing a bloodlust vampire i want to see blood everywhere, people loosing legs and head all the time
but like pointed out by other poster: in BG&E any amount of blood would ruin the game.
Wolverine is a slaughter machine. he chops people like fries: cuts heads, arms, eyes off all the time. A game about him should feature as much gore as possible although being realistic at the same time.
but blood in monkey island is a big no... maybe little for a joke.

I really don't care one bit about the gore level in a game, whether high or low.

I have to agree with you completely. I've been reading the comics for quite a while, especially in the 90s. I mean, look at the Weapon X arc by WIndsor-Smith. It's about a man who's tortured (literally and figuratively) and changed.
The X-men books tend to have a different feel than the solo book (and Marvel Comics Presents), which I think less people seem to be familiar with. The Origins movie was going for these kind of themes much more than the previous X-men films. The guy was an assassin. Assassination tends to be bloody. It also revelas that wolvy was a shady character. Look at the Cyber arc right after Weapon X in MCP. Ol Canucklehead gets tagged with an hallucinogen in the jungle and has to fight a psychotic old enemy and save his girl pal, who's heavily involved in organized crime.
If it was Super Mario Wii or something or a game where it didn't match the brand at all decided to throw in the occasional decapitation, I'd think otherwise, but in this case I think it's wholly appropriate. It's an action game targeted towards older teens and adults, not kids. It has an 'M' on the box, too. Personally, as much as I'm not a fan of the game (it is more than a tad derivative of GoW in terms of gameplay and has that good-enough licensed game feel) I think it does a decent job with the portrayal of the licensed material.

That's why there's such a thing as variety. If it offends you go play Mario Galaxy.
I do believe however that most games have taken the route of more gore the better. It seems to have taken the place of an actual story.

My sentiments exactly. Don't mind it unless abused and my impression of a game decreases the more obviously over the top it is.

For me, it depends on how it's presented. If it's just gore porn where the point is to show how cool, dark, and gritty something is by how much blood my hypertensive enemies can spew all over the scenery, then I'm not interested. If it is enough to provide visual feedback, that's no problem. If there is feedback without blood, that's fine too; cartoonish violence seldom includes blood even as someone is flatted by a steamroller.
Gore in games is not a matter of depicting reality anyway. No game I have seen has blood that behaves realistically. It is all theatrical: gushing by the gallon, coagulating quickly and thickly on blades, or pooling on the floor no matter what the surface is. It all communicates something in the context of the game. Since it does communicate something, I think there are good and bad uses of gore as there are in any artistic medium (more so for games, as they require our active participation). To argue otherwise would be to argue that games and what they depict are essentially meaningless, and to cede the argument that games are artistic.

I don't play all action games (no story etc) so I don't know much about this.
But personally, I don't care. Let the Evangelists and the politicians whine, it's not really hurting anyone is it?

I require Manhunt-level games regularly as a way to relieve stress. More blood and gore gams please...as long as theblood and gore makes sense in the actual game.

It depends on the game and it's purpose. I can't image Doom without gore, but don't care about it in Mass Effect, for example.
As a matter of fact, any game that relates to action movies, horror movies or kung fu movies should come with loads of blood.
Barbie games could use some too. And zombies. Lot's of them. :P

Funnily enough I was saying the other day how I thought games had become less graphically violent since the transition to 3D. There's no modern equivalent to the Cacodemon or Mancubus death animations, for instance. Even the Protoss Dragoons in Starcraft have more ick factor than anything I can think of from the past ten years.
Game blood used to be so much more viscous; these days it's limited to splatter decals and magical-looking particle effects.

A good example of the nerfing is Half life to HL2.
In the first one you could hit the bodies with your crowbar and explode them into gibs, but in your standard hl2, this has been removed.
The only time blood has got in my way was in Fallout 3, when you blow someone up near to you and get blood in your eye.
It sits there as a few little drops, as if your face is a big camera lens.