also that 200 quid piece of hardware can do wonders.
I haven't seen a PC game blow it away. and the 360 costs less than your graphics card.
Not everybody will drop 1500 just for a PC, but 200 quid for something which will give you the same, maybe even better results, then yeah that is easier to justify
The whole experience is just better. For example when bioshock comes out in a couple of weeks, mines will land on my doorstep i will go put in it my 360 and it will be playing in what a minute? and will look just as good as pretty much any PC kicking around. Also have all my online functions without having to alt tab etc.
But for the PC you will have to 10-15 minute install, then hunting to see if there is a patch, then setting it up so it runs nice.... maybe after 45 mins you might get to see the game.
Just an example why folk like it too