IF it is true and the fusion system is like iOS/Android systems, then that means digital games on 3DS/WiiU/VC/etc will work on said system simply by logging in with your NNID.
That means day one it already has a very large library. Personally, I think we'll see this, this gen with VC titles once the final part of the NNID system is upgraded. Maybe with this year's update.
Then all they need is a couple 1st party launch titles (two studios at a min) as well as whatever 3rd parties can support for new multiplatform content.
So I don't think their fusion concept will harm 3ds/wiiu support at this time. At least not like it did for ds/wii in 2009/2010.







