your evidence doesn't support your claim.
sony also publicly stated they are working on their next console,.. that doesn't mean that ps4 is being replaced next year. R&D can span 3-6 years. stating that are working on a home console doesn't provide any evidence that NX is a home console.
edit: evidence your claim is baseless.
Dec 2014: http://www.kotaku.com.au/2014/12/nintendo-is-working-on-new-console-ideas-says-miyamoto/
March 2015: http://www.theguardian.com/technology/2015/mar/17/nintendo-new-gaming-hardware-platform-codenamed-nx








