I have a friend who is buying a Trek full carbon XC frame.
Does anyone know the benefits of carbon for MTB'ing?
I've got a Road background so I know about the vibration dampening benefits, but is carbon really that good for XC racing?

Brian

Carbon is very suitable for the production of XC frames, but it all depends on the manufacterer. Carbon frames can be very forgiving and flexibel, but also very stiff (f.e. the Giant MCM, so I have heard).
The possible benefits are great: Quality carbon frames can be forgiving in some areas, but very stiff where you need it, f.e. at the BB.
I would read a lot of reviews of various brands to find out about their different ride characteristics.

JK

I have a Trek OCLV frame and I can´only recommend it to another mountainbikers. It's really nice ride.... takes the top of the bump and still feels hammerstiff when you're out of the saddle and hammering! And a good look haven't made it worse

I have a trek 9.8 and its the best XC bike on the planet, no hardtail will ride smoother!! I'll e-mail you a pic if you want