What I'm most curious about now is how big and how hot this SoC is...
Looking at Trinity for example, you have the same GPU clock, but the PS4 chip has 3 times the CUs, 4 times the ROPs, 3 times the texture units. The top of the line Trinity is a 100 watt part and measures 246mm^2. Now, on the CPU side, with Jag cores instead of Piledriver, they will save some power and space, but I would guess the hottest and largest part of the APU is the GPU side, so I wonder what the power and die size are going to be like.
If we guess the CPU power at 40W and the GPU at 60W for Trinity, for example, the raw numbers put you at 180W for just the GPU on PS4. That obviously can't be right. Now, 8 Jag cores probably aren't going to be more than about 20W, so thats some wattage opened up for the GPU side, and they probably will only be about 30-40mm^2 or so, so you're gaining some die size there, but not 3x. Eyeballing the Trinity die, I'd peg the CPU side at about 80mm^2 or so. So that gives you 40-50mm^2 more for the GPU side, but the Trinity GPU being 120mm^2 or so of the die, that doesn't even give you an extra 50% of the Trinity GPU.
Unless there some kind of magic voodoo going on here, I can't see them getting below 400mm^2 and 150W, which will make for some interesting cooling challeneges and some expensive dies. Heat piped cooling with some good fans are going to probably be required. I fully expect the price to be $550-$600.
Edit: Don't forget twice as many memory controllers and GDDR controllers instead of DDR3, which adds even more to the mix.