Sony's executive vice president and chief financial officer Masuru Kato let slip that development of the PlayStation 4 is already under way, contradicting a previous statement by Sony Computer Entertainment boss Kaz Hirai.

Back in March of this year, Hirai had said that "a near-future PS4 or next-generation home console is not something that we are even debating now."

However, Kato revealed otherwise during an open conference call to investors: ""For the home equipment the PS3 still has a product life," he said. "But this is a platform business, so for the future platform - when we'll be introducing what product I cannot discuss that - but our development work is already under way, so the costs are incurred there."

Traditionally, Sony has released a new generation of the PlayStation every six years, with the PSOne (known then as merely the PlayStation) coming in 1994, the PS2 in 2000, and the PS3 in 2006. However, the company has always upheld the notion that the PlayStation 3 would have a much longer lifespan than its siblings, especially as it is upgradeable through firmware patches. Some have even touted a 10-year lifespan as a more realistic notion.

But, Nintendo is pressing forward with Project Cafe, its successor to the Wii. And there are reports that developers are starting to get their hands on prototype kits of Microsoft's next-generation console, even though the American manufacturer had also previously stated that the Xbox 360 was only in the middle of its lifespan and will continue until 2015.

So, considering these facts, and the recent public relations and consumer backlash provoked by Sony's disastrous PlayStation Network downtime and hacking scandal, we'd be more surprised if Sony wasn't already working on a PS4... And we may even see it sooner than expected.