Xbox One will not be backwards-compatible with Xbox 360 titles - including digital games downloaded from Xbox LIVE Marketplace, Microsoft has confirmed to VideoGamer.com.
Instead, only video and music content downloaded on Xbox 360 will be transferable to Xbox One.
Speaking to VideoGamer.com this evening, Xbox UK marketing director Harvey Eagle claimed that Xbox One and Xbox 360 were two different systems designed for different games.
He also confirmed that Gamertags, Achievements and Avatars will transfer over to the new console.
Source: VideoGamer.com Interview