Doom Beta to be Available on PC and Next-gen Only
According to an FAQ on the official Wolfenstein website, the beta keys will be included inside the boxed copy of the game. Once you redeem the code, you'll be registered for the beta and can participate once it begins.
Just note that the console on which you purchase Wolfenstein and redeem the beta code correlates to the console on which you'll play the beta. So if you buy the Xbox 360 or Xbox One version of Wolfenstein, you'll receive a key for the Xbox One beta. If you buy the PlayStation 3 or PlayStation 4 version, you'll receive a key for the PlayStation 4 beta. And of course, all PC versions will get you access to the PC beta.
To put it simply, the beta will only be available on PC, PlayStation 4 and Xbox One. Check the link above for more info on the beta and look out for Wolfenstein: The New Order when it's released on May 20.