Chances are you already know this and have rushed out to buy it - but in case you didn't know - Gears of War 3 is in all major retail outlets nationwide and in most regions around the world. Epic's Xbox 360 coop shooter tells the final chapter in the Gears of War trilogy from Epic and provides more multiplayer action with or against your friends.

“Today’s launch of ‘Gears of War 3’ kicks off the biggest holiday season of blockbuster games in the history of Xbox 360,” said Microsoft Corporate Vice President Phil Spencer. “The team at Epic Games has raised the bar yet again and we’re extremely excited to see fans around the world get their hands on the game and jump into the action.”

Gears of War 3 promises a story written by New York Times bestselling author Karen Traviss, an all-new campaign, and an improved multiplayer experience

“This is our biggest ‘Gears’ game yet, and even though it’s the third installment in the trilogy, it’s the easiest to jump into if you’re a new fan,” said Epic Games Design Director Cliff Bleszinski. “We’ve added more cooperative gameplay options and built in accessibility features throughout the game to make it approachable and fun for new players and series veterans alike.”

Gears of War 3 is available worldwide (except in Japan, where it will release on Sept. 22), in three editions – Standard ($59.99 USD), Limited ($79.99) and Epic ($149.99). For additional details on the game, visit gearsofwar.xbox.com .

On a related note, Calibur11 announced that its exclusive Gears of War Vault is hitting retail now. The Gears of War Vault is a custom, interactive case for the Xbox 360 Slim that features a high-definition “Bleed-Out” finish, controller cradle and an LED Crimson Omen. Calibur11 is also hosting a special Gears of War 3 contest here . The Gears 3 vault retails for $89.99. Find out more at calibur11.com .

Finally, rental company Blockbuster today announced all in-store purchases of Gears of War 3 will include a pass for free unlimited in-store rentals of games and movies for a month. Gears of War 3 is available today and the promotion will run until Oct. 7, 2011. For more info, visit your local Blockbuster store or www.blockbuster.com .