Nintendo has survived NEC, SNK, Atari, and Sega just to name a few. They aren't going anywhere any time soon. It's more likely that Sony or Microsoft leave the market before Nintendo does. Nintendo has proven several times that they can support a console on almost 1st party alone. Sony and Microsoft 1st party games are great, but they just wont keep a console going on their own.
Edit: Opps forgot about Magnavox, Coleco, Mattel, and the 3DO Company.








