The vibe I get on this board these days is that every dev and person associated with the industry is expecting less potent hardware and better software platforms. The future isn't seen in hardware. Whereas many others are still expecting the console businses to carry on as it has done the last four generations without change and they want the console companies to lose massive amounts of money on hardware. The business side of picking next-gen tech doesn't not point to awesome hardware IMO.
Thing is we can expect there will be no blu-ray scarcity uber costs, thus the disc drive will not add significant costs to nextgen consoles. There is likely to be no uber investment in cpu R&D or gpu R&D, and hopefully no horrible yield, as occurred in this generation.
Microsoft released an uber console, losses obviously weren't that bad, if they were the red ring issue costs would have led to catastrophic losses. What we saw was aggressive pricing and profitability, they even managed to increase initial ram at the request of developers.
Another of the high costs is the Hdd, if flash memory prices continues to fall, a 16GB built in storage could possibly replace this costly and highly damage prone component.
We can also assume amd gpu licensing will match powervr(cents to a dollar vs nvidia's 5 dollars).
So the question is with most costs gone(heavy R&D, low yield issues, high disc drive prices, lower licensing prices e.g. vs nvidia), and using slightly customized parts what can they get within 300-400 dollars?
We know that cpu performance still exceeds state of the art pcs in some parameters, and the gap is likely to grow even bigger as moore's law slows. The power/heat constraints are the main issue, especially with regards to the gpu. Is there any design that can offer very good performance within such constraints?
The powervr thread suggests some gpu designs can likely offer a substantial nextgen(10~)jump within given constraints.
Either that's not true, or we can assume amd can match performance within the same constraints.
EDIT:
BTW,
IT is likely that console manufactures are privy to the differences between two chip solutions and SoC solutions, like happened with the 360(256 vs 512MB ram), dev. input will influence decision. Either the 2 chip solution will not offer a substantial jump in graphics, or it is likely to be taken and later scaled to a SoC. It would be ridiculous for a console manufacturer to do otherwise, as there would be a substantial gap from day one with a competitor that chose otherwise in the presence of the same decision.