..Games.

I believe that's what has really been driving the increase in power in PC desktop hardware - just try playing FEAR on a terminal or a 386.

For the forseeable future gamers (and those who suffer from crap BT DSL-plus latency) will still want/need desktop machines with a load of processing power and quality, secure, efficient operating systems and the applications to go with them (or Microsoft Vista and Office).

PC's are increasingly used for entertainment. People will want this undiluted, only their ability to pay will stop them. On the other hand, a thin client would in increasingly occupy work desks in enterpises. Thin clients would reduce costs and increase productivity.