THQ announced today MMA fans can get in on the Undisputed action early by registering at ufcundisputed.com and signing up to play the demo. Those that take part will be able to download the demo on Xbox Live and the PlayStation Network tomorrow, Thursday, April 29.

Undisputed 2010 brings a few new tricks to the UFC's videogame franchise, including increased fighter customization, an upgraded career mode, new fighting mechanics, and improved online options.
From THQ:
The playable UFC Undisputed 2010 demo allows players to jump right into Exhibition Mode or challenge friends offline in Tournament Mode, and will feature four Light Heavyweight Fighters – Mauricio "Shogun" Rua, Lyoto "The Dragon" Machida, Rashad "Sugar" Evans and Quinton "Rampage" Jackson.UFC Undisputed 2010 is set to launch for the Xbox 360, PlayStation 3. The PSP gets Undisputed on December 31.

