I get the impression that Sony, Microsoft, and Activision reeeeally want you to buy a new console.
Activision has announced a cross-buy deal in which all PS3/Xbox 360 digital purchases of Call of Duty: Advanced Warfare will also net you the PlayStation 4/Xbox One version as well. This applies to all purchased DLC (season passes included) and any stats you might rack up—it all transfers over.
Once you have the game, you need only enter a code that comes with it to claim your other version. The deal will expire at the end of March 2015, so keep that in mind if you like sitting on codes for months on end or your birthday is in April (like mine!) or something.