Nintendo has many games in development close to release. They are not announcing anything because they need something to generate hype for Christmas 2013. They will be battling two new systems for attention. Those systems will be new and fresh and more powerful, but also likely expensive, in limited supply and with limited software support. Nintendo will counter with a system which is readily available and cheaper. But most importantly with a flood of high-quality software. You can expect a 3D Mario which is graphically stunning, A Retro game which is more mature and also pushes the limits graphically, and some new innovative things designed to appeal to the mainstream. They can't announce these things or they will be old news by fall. They also don't want to be copied too soon like they were with the Wii remote. Launching first gives you an edge, but it also allows competitors to react. I would expect that the 3D Mario will be pushed to be a game that makes jaws drop. It will be the game that makes people say that WiiU is not (dramatically) inferior to the newer systems. Retro's game will also probably have a fine level of polish, something akin to Naughty Dog's games.
