I commented a couple of weeks ago on a thread where I talked about brand equity, and iTunes is a perfect example of this -- it hasn't been solely about music in years, it has a half dozen bolted-on functionalities and it's in desperate need of a refresh. And yet the iTunes brand is so strong that none of that matters.
The only reason I still use it, really, is because the last time I tried using something besides iTunes to sync my music to my iPod, it nuked the whole library. As far as I know, it's the only fool-proof way of synching my iPhone with my iTunes library (which actually lives on my iPod, because its audio jack died.)
I'm not aware of another media program that does half these things half as well. But feel free to enlighten me.
Safari is the browser for "all weird stuff out there" and the iTunes app is the browser for "media shop and media I have bought".