Maybe in MS and Sony's case, but Nintendo makes a hell of a lot of money when they release their new consoles. It would be in their best interest to continue to release new hardware. And if they release one, Sony and MS will have to follow suit.
You can't continue to drive sales and expand markets without entering something new or appearance of "new". Otherwise the market will crash. It happened back in the 80s. For an analyst, this is not a very smart prediction. Sure they'll use up all your "revision" options but eventually they'll have to release another one. Let's hope they don't wait til such extremes to do it.
I think all we'll know after this generation is that generation life cycles will probably be longer than the traditional 4-5 years.
