I agree with Boris here.
I have a Q6600 (still it's an OK CPU) but only 2GB of RAM and a ATI 2900HD graphics card which let my system down. Sure I could stick a newer gfx card and another 2GB of RAM but I don't have the money.
My PC works for Battlefield Play4Free, even played through Crysis 2 on medium graphics and it was fine, works for Flight Sim X when I can find time to play it and also runs my movies and web browsing fine. All the fancy DX9934343 games with 3483x1231389438943 resolution pixel maps for 1024bit textures I will just buy for the PS3 and play on that.
I will eventually upgrade my PC with new hardware but that's not important because for my needs at the moment it's fine, and it's the same sort of story with everyone else.
I can't justify spending so much money on a PC when I can buy a game which will work fresh out of the box (no need for any "upgrades") on a console.
So what the graphics are a little worse, they're only probably 10-20% (at worst) better on a PC where as the cost difference between the console and the PC is probably 75% so tell me who's the smart one....