I had a blast with the first UFC Undisputed 2009 and am looking forward to the new improved 2010 version. I really like the demo below with the new sway system. Its definitely different in the fact that you don’t have to be cast into a fighting style completely, you can take different things from all the styles and pretty much create your own style. It really looks like THQ has put a lot of time into the game and it just keeps getting more and more polished.

New Sway system, cage physics and submission system.

UFC Undisputed 2010 Fight Tutorial

BloodyElbow.com has a demonstration of the Tournament mode, new career mode, and some demo of the new submission moves. You can preview them at this location.