Check out an official trailer to the Transformers: Dark Of The Moon video game for PS3 and Xbox 360 by Activision and High Moon. This was released at the Toy Fair 2011 and put up by IGN.
The video game version "leads in to the events of the movie and takes players through High Moon's versions of Earth-based locations like Siberia and Detroit."
The game will have a new transformation mode called "stealth force" and also be playable online. Not much is known about the online multi-player aspect, other than a similar "competitive component" ala War of Cybertron. Also, according to IGN, the online version will be Transformers.
Transformers: Dark Of The Moon will be available this summer.