Microsoft announced all the information you'll need for the Gears of War 3 beta beginning in April. They've provided dates and details on the beta's content.

Starting on April 18th, players who picked up the "Epic Edition" of Bulletstorm will get an exclusive one-week preview of the beta. They'll be able to play Team Deathmatch on four new maps (Thrashball, Checkout, Trenches and Old Town). Two of the maps were selected by fan voting on the Gears Facebook page.

The full public beta will begin on April 25th. Any gamers who pre-order Gears 3 through GameStop will get access to this phase. Two new game modes, Capture the Leader and King of the Hill, will be added to the beta over time. Special events and playlists will be included as well.

Participating in the beta will unlock exclusive content for the full version of GoW3. Here's the list of prizes you can earn:
•Beta Tester Medal – Complete one match in the beta to unlock the Beta Tester medal, which will carry over to your gamer profile in the final game. The Beta Tester title will be featured in the “Gears 3” multiplayer lobby as well.
•Thrashball Cole – Complete 50 matches in any game type to unlock the Thrashball Cole character variant in the beta. Once unlocked, complete 10 matches as Thrashball Cole during the beta and the character will carry over to your gamer profile in the final game.
•Gold-Plated Retro Lancer – Show your ultimate “Gears of War” fandom by unlocking the Gold-Plated Retro Lancer. Complete 90 matches in any game type to unlock it for the beta, and score 100 kills with it once unlocked to carry the exclusive weapon skin over to your gamer profile in the final game.
•Flaming Hammerburst – Complete one match by Sunday, April 24 and unlock this weapon variant.
•Flaming Lancer – Complete one match during the week of April 25 and unlock this weapon variant.
•Flaming Sawed-Off Shotgun – Complete one match during the week of May 2 to unlock this weapon variant.
•Flaming Gnasher Shotgun – Complete one match during the week of May 9 to unlock this weapon variant.
The press release mentions that you'll get beta access regardless of whether you pre-order the $59.99 Standard Edition, $79.99 Limited Edition, or $149.99 Epic Edition. There's no mention of what the Limited and Epic bundles will include.