I do use itunes. Great service, and if I want it to be an mp3 instead of mp4, I just use ijukebox conversion software.
But, I would never buy an Apple computer unless they became much cheaper.
Of course it depends on what you're looking for, but check out the iMac or Macbook Pro in comparison with similar systems (now that they're both Intel, we can compare apples to apples). A Dell XPS 400 equipped like the iMac but missing bluetooth and wireless and not in the space-saving form factor is more expensive. Put either Macbook Pro (1.67 GHz and 1.83 GHz) against a Dell Latitude D810 at the same price and there's no contest -- the Mac is smaller and more powerful, has a faster DVD writer (slot-load too), and has that cool backlit keyboard. Both of those Macs also come with a lot more standard software.