Xbox One and Xbox 360 cross-gen titles will have separate achievements, so all of the cheevo-hunters out there can get more score by completing both versions of the same game if they really, really want to.
Speaking as part of an IGN 'Ask Me Anything' session, Xbox One architect Marc Whitten Said of the dual achievements, "Every game has its own set of achievements, so if you're playing Call of Duty: Ghosts on Xbox 360 and on Xbox One, you can earn a separate set of Gamerscore in each game,"
"But on the Xbox One version, you're getting a much richer set of features, such as seeing your achievements progress on the Xbox One console, being able to unlock new achievements throughout the year, and earning real prizes inside and outside of the game."
Would you actually, ever consider doing both? Let us know.