I'm not sure a game publisher needs a kit at this point - at least not for the XBOX. They can code their games against an established set of APIs (DirectX 11 or some third party engine like Unreal) and when the XBOX SDK for the new console is available - a little porting and a recompile should get them going.
While they can't count on any particular feature being available it's a fair assumption that alot of the new features not currently available on the XBOX will be made available. If it's not they can choose to not ship the game on that platform, or gimp it so it looks crappier
As for a 2012 to 2013 release date for a new console - I think it's totally possible - Especially for Microsoft. They sign non disclosure agreements with other companies all the time - usually enforced with huge financial penalties - its in everyone's best interest to keep things tight lipped
While they can't count on any particular feature being available it's a fair assumption that alot of the new features not currently available on the XBOX will be made available. If it's not they can choose to not ship the game on that platform, or gimp it so it looks crappier

As for a 2012 to 2013 release date for a new console - I think it's totally possible - Especially for Microsoft. They sign non disclosure agreements with other companies all the time - usually enforced with huge financial penalties - its in everyone's best interest to keep things tight lipped






















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