Not much I'd guess - the cost of high quality graphics are going to become a limiting factor moreso than hardware (possibly) so going much further than they currently do is unlikely - unlike previous generations which were limited by hardware. Obviously a few of the newer DX enhancements will make it in but they don't make a massive difference in my view.
I think you've got your list wrong in some sense though, each generation raised the ceiling that the code was limited by, whereas in the days of my youth games were limited by the machines they ran on only a few games now (the most expensive to make) can poke the sky, further lifting of that limit in generations to come will mean fewer games having a problem with it - without massive development budgets to waste time on making their graphics that much more photo-realistic when really it doesn't matter, I mean, really, if it were, how did gaming ever take off in the first place?
One thing I would like to see is the move away from discs as physical media - nand flash is so cheap and capacious that we could see a return to cartridge style game forms, plus that way no one would have to pony up royalty to Sony every time a machine is sold or a disc burnt.
I mean I walk around with a 16GB micro-sd card in my phone and another in a USB adaptor which is little bigger than a USB port (literally only half of it hangs out the socket) - games wouldn't need to be that small so could utilise larger, cheaper chips found in USB Pen drives and still benefit from improved load times over spinning media.
