the next year game argument is flawed in that a pc graphics are improving via a better gpu a more powerful cpu!
next years game will run on this year specs the same way it will run on a ps3 and 360.
the only difference is the game wont look as great as the latest greatest hardware.
because games are scalable they do optimize console games line by line taking out putting in for a better looking game
like fewer enemies flowers trees.
also most games are made to run a middle pc card being $400 SUPERCARD or a midrange $200.00 card.
I picked up a 9800 gtx for $170 6 months ago and it kills on cod4 over both PS360 more enemies and effects.
still I agree console gaming is cheaper overall for upgrades and the games you get over the life of the console.