I have used iTunes ever since it was Casady & Greene's SoundJam MP (retail).
ITunes is one of the absolute best free applications around.
I must say, however, that it is beginning to become a bit cumbersome and
bureaucratic. iTunes 7.6.1 froze me out of my account until I updated to the latest
iteration of 7.6.1xx..i.e. it forced the update...
(perhaps there was some un-announced security vulnerability)
Plus, I think about 50 percent of the time I have to re-agree to the Terms in order to
spend money at the iTunes store.