Like always, PlayStation are going all out this time, but Xbox will wait and watch and then when they bring there console out it will be better than the play station.
No, Microsoft already stated they have no plans to upgrade to GDDR5, and they'll stick with DRR3 for the time being.
Imagine, a 8GB GDDR5 GPU in PS4.

just fuckin epic!
Also, you can do some 3D animation on it with move controllers, they showed a glimpse of that in trailer.
:ps: For those of you thinking it'll be extremely expensive due to hardware, I read on Cnet -
''When it comes to consoles, hardware is always sold at a loss, its software where money is made.''