The demo for latest title in the Need for Speed series has sneaked onto Xbox LIVE Marketplace. It’s a 654.64MB download and is available in all regions.

Demo description: Compete at the highest level of street racing. Experience the intense rivalry of Grip Racing and prove yourself in the all-new Speed Challenge - the ultimate test of speed and control.

Need for Speed: ProStreet will be released on November 14th on Xbox 360, PS2, PS3, PC, DS and Wii. The PSP version will be released a few days later, on the 18th.

Also, the Guitar Hero III: Legends of Rock demo that Microsoft announced yesterday is available now as well.

[See also: Need for Speed: ProStreet gallery]