The majority of the console demographic would never buy a PC anyways.
1) Too expensive
2) Can't do in house multiplayer
3) Can't rent games

I believe all those points are invalid, at least for here in the UK anyway.

1) I've seen a brand new PC (obviously not top of the range, but near enough) for sale for about £400 including monitor, keyboard etc etc. Next gen consoles will retail for close to £300. Games on top of that would be £35-40 a pop, so you would still spend about £400 on a console. And thats without buying an extra controller for those multiplayer games.

2) PC games can do inhouse multiplayer. Granted not many, but a few do offer the ability to have either a "hot seat" function or a split screen. Virtually all PC games offer online playability to, and considering most people do have some form of internet connection that is adequate to play online, there's no excuse for "But PC games can't do multiplayer".

3) You can rent PC games. Fewer places are doing it now because there's not as much demand as there was back a few years ago, but you can still rent games.

I still firmly believe that two of the main reasons why people are buying/playing so many consoles/console games is because:

1) It's easy. Theres no need to update drivers on the console, there's no need to pull it apart or send it in to get fixed, and there's no need to buy expensive OS's.

2) Marketing. They market the Xbox and PS2 as being party pieces and great fun for everyone, and as such most people conceive PCs to be a loner type thing. Also how many PC games do you see being advertised? There wasn't a SINGLE Doom 3 PC advert when it came out. As soon as the console version was about to be released, there was a huge marketing campaign.

Although i don't like it, i know the consoles will eventually push out the PC into the realms of totally niche games. There are very very few good driving simulators and RTS on a console, even fewer flight sims, and as such people will turn to the PC as a niche system. Even a decent FPS is hard to find (due to the controls) on a console, but then again it's the same for the PC....just for different reasons.