Bulletstorm is set to drop in just a couple of days, and Xbox 360 owners that purchase the Epic Edition of the title will get access to the Gears of War 3 Beta with the game. You ticket in, is your Bulletstorm disc. What should be very similar to the dynamic that the Halo: Reach beta had, you will need access to the disc when the Gears of War 3 beta finally rolls around.
The beta for Gears of War 3 is scheduled for sometime in April, so plan on holding on to Bulletstorm at least until then. Purchasing the Epic Edition of Bulletstorm is your only sure fire confirmed way to gain access to the Gears Beta. Bulletstorm is getting ready to launch on February 22nd for Xbox 360, PC, and PS3.