Hang on a sec.....don't consoles run at approx this spec
Low-med settings
none-low AA
640p-720p resolution..
Now bump it up to ULTRA, 4-8XAA, and 1080p and no wonder a PC can be under pressure.
Let's be real, the difference between graphics of consoles and PCs is negliable at best, aside from a few games. Take a game like gears of war. The rec system req. are a dual core intel core duo or athlon x2 (both of which are more powerful than the xbox/ps3) 2GB of ram not including 512MB of vram (even taking 1GB for the OS, you're still at double or more memory requirements) and an x1900, a whole generation above what's in consoles.
I'd say on average, for the same resolution and relatively same graphical settings, a PC needs 30-40% more hardware. So while not a whole lot, most of us are used to running 2,3, even 4 year old PCs and running most games pretty fine. My point was that it will hit reality real quick when that doesn't happen anymore and we all have to upgrade to high end machines again. I foresee a lot of complaining a la crysis style when new consoles are released, ie "this in unoptimized" when in reality it's just that their machine sucks.