There was an article this weekend brought to my attention, about iTunes, that I thought perfectly explained the problems with the platform. The article is called ITunes Music Store. Facelift for a Corrupt Society. I definitely recommend checking it out.
Of course, if you do this research yourself, or you’re an artist, you will or have found the same results, but if that’s not the case, his main points against iTunes are that it’s too expensive, there is poor audio quality, and they take too high of a cut from sales. (horrendous paraphrase..apologies)