As of yesterday, Halo 4 has been available in stores such as Best Buy and GameStop. The game was on pre-order from the retail stores for a while, it was available in the Xbox 360 Limited Edition Halo 4 Bundle or the game by itself.
Amazon had an $10 Instant Video Credit and Exclusive Pre-order Bonus, if you had pre-order the game from Amazon you would have received Halo Infinity Multiplayer with the Amazon exclusive customizable “Web” armor skin.
The colors of the armor skin can be customized to fit your personality, but Halo Infinity Multiplayer will revert players to default colors in some competitive modes. Your Amazon Instant Video credit will be automatically applied to your account when your order has shipped.
If you didn’t pre-order, you can walk into a Best Buy or GameStop to get the new sequel of the popular gaming title.