I'm confident that the PS4 and Xbox 3 will debut at E3 next year.
MS might push for a holiday 2013 release if that 2 year old leaked document is to be believed accurate but I'm not sure how they can launch a $300 machine with kinect and be up to 6x as powerful without taking a loss per system and/or risking faulty hardware. A $50-$100 loss might be what it's looking like. MS can do it so I wouldn't be surprised. Releasing year of and during the holiday would generate good buzz in their biggest markets the US/EU. Buzz they will need since the 360 is lossing sales strength, a new system could be justified in 2013.
Sony will come last but by less than year, getting a headstart of the holiday season in spring or late summer 2014. They don't want to wait too long after the Xbox 3 to launch but economically there might be good reason to wait even longer. The PS3 has strong sales for an old console in the off season and could indicate continuing sales even through 2013/2014. Sony could hold off till holiday 2014 which would ensure them more time for there company to strengthen from its transition and their big developers to provide blockbuster launch titles they would need to pull off a late launch. Releasing earlier would force them to reduce the hardware capabilities and risk being outgunned next gen by MS ability to throw money into the Xbox 3. Sony would be better off leveraging themselves against the Wii U for multiplats with PS3 than to release PS4 early just to be competing with PS3 on top of next gen systems. The PS4 will need to be at least as powerful as the Xbox 3 and they won't pull that off by jumping the gun and risking one of the few profitable divisions they have.
It will be interesting to see if PS4 or Xbox 3 will be the more powerful/better machine. MS has the money while Sony has the time.
Before the PS3 everyone was nice to me :(
