I hate iMacs as well! But I am a avid Mac user, I guess it comes with being in the grahics industry. Don't get me wrong, I have built a few PCs as well, matter of fact, I just completed building a fairly fast AMD machine, hence the reason I have been preoccupied lately.
I just read an article on the new G5s. This was an interview with a PC reviewer and while some of the comparison numbers Apple reported on the G5 may have been rather inflated, this tech reviewer did state that the G5 should give any desktop PC a run for it's money. I've been trying to locate that article and as soon as I locate it, I will post a link here.
I do think that Macs are WAY over priced considering that you really can't alter their configs as you can when building a PC, but if you match feature for feature, normally the prices level out a little.
There is a strong following for Macs in the audio field, I do remember a very long conversation I had with Trent Reznor after the 1st Lalapalooza in Atlanta. He does all of his work on a Mac.