Despite rumours in the blogosphere that Sony is already hard at work on a PlayStation 4, Sony chief Masaru Kato said the PS3 still has a long shelf life ahead of it.

The rumours started at a financial briefing over Sony's 259 billion Yen loss for the last fiscal year. Kato remarked that the PS3 has a product life but, "this is a platform business, so for future platforms, though I can't say what we are going to release when, our development work is under way".

That was just about all the blogosphere needed as confirmation that a PS4 was on the way. However, in an interview with the Wall Street Journal, Kato denied his intent was to indicate a fourth PlayStation was on the way. Kato said the only new platform mentioned was the NGP (Next Generation Portable).