This is kind of a common thing that I think a lot of people throw around without understanding context ... that if you release a successive console/handheld too soon after the previous one you will suffer in the future. 

But do the facts actually back this up? I would say no. In fact the most successful game platforms from Sega, Nintendo, and Microsoft all came succeeding relatively short (3 1/2 years or so) console cycles:

Sega Master System (1986), Sega Genesis (1989)  - Most successful Sega console ever (Genesis sold over 300% more than the SMS)

Game Boy Advance (2001), Nintendo DS (2004) - Most successful Nintendo game platform ever (DS almost doubled GBA LTD)

XBox (2001), XBox 360 (2005) - Most successful Microsoft game platform (360 sold 4x as much as the XBox)

And I'm starting to think it's unlikely the XBox One beats the 360.

Yes there is the Dreamcast ... but people need to understand a few things -- the Dreamcast actually didn't do *that* badly early on, it had reasonable launches in most territories. The main problem with the DC was certain third parties, especially EA, would not support it and more importantly Sega simply ran out of money to keep supporting the system. 

Also people need to understand what clusterf*ck Sega's transition was in the mid-90s, it wasn't just because they stopped supporting the Saturn, they released the Sega CD in 1992, then the 32X in November 1994, then the Saturn without any warning in April 1995 (!). They literally had to shoot themselves in the foot three times, lets not act like that is the same thing as a company maybe replacing one platform in year 3 or 4. 

People really need to stop quoting this idea as if its gospel, or at least understand what they're talking about. 

huh?
i want the ps4 to al least go 5+ years.

Apple

Who said that?

No new Nintendo hardware until 2016 / 17.

But when people talk about replacing the Wii U, they mean replacing it after only two or three years on the market without getting some major IPs on it. That really is too early.

Yup corporations can "flip the boardgame" if they don't like how the game goes and start anew without damaging the brand. If the next console is great then the fans will forgive and move on. That is exactly what MS did with 360 releasing early and Nintendo (from a business perspective) with the Wii.

One of the only good things I can think of that will come from PS4 dominating at the expense of their competition. Nintendo and MS will start a new gen MUCH sooner then last gen and force Sony to react, most likely late.