iTunes radio is pretty good out of the box, but there are some annoyances that will keep me subscribing to P1 for now:
1. Can't ditch the Featured Stations - I have zero use for them and they take up a fair amount of prime screen real estate promoting a lot of stuff I will never listen to or buy.
2. The selection algorithm isn't as refined (even though the song d-base seems larger) - I've had too many repeats already in a short time of use in a very broadly seeded Reggae category.
3. Inconsistent streaming - I realize that it's early days and Apple's servers are likely getting slammed, but I had a lot of stuttering and drop-outs last night.
4. I don't trust the reliability of iTunes Match - annoying stories abound and I want no part of those.
5. As someone pointed out above you can't combine stations into a cross-genre mix.
Hopefully they get it together on iTunes Match and give us the flexibility to kill all the Featured Stations if we want. If they can manage to do both of those things I'll let go of Pandora, but given Apple's history with online services and user customization, Pandora will probably be getting my money for a while to come.
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