I'd never heard of this service until I was surfing apps on my blackberry.
Unfortunately my bb doesn't have 3g internet service, (lame) so I can't leave the WiFi hotspot.
but most other phones work fine everywhere, my friend has Tmobile with a myTouch phone- works great in his car through the bluetooth on his head unit. But you could use any other form of connection if you wanted to.
He has a really nice system in his truck and the music comes through nice and crisp with good low end.
Nothing like some internet radio services I've heard. (all sizzerqueep) i made that word up.
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It's a cool service, you type in a song or artist you like, and it makes a station on your phone that plays music from that artist and artists like them. even obscure music. you can have a bunch of stations and if you don't like a song you can either skip it or ''thumbs down'' it and go onto the next song.
The only problem I had was, you only get 6 skips or 'thumbs down' an hour with the free version...
but you can restart the app and it clears the 6 back to zero.
http://blog.pandora.com/faq/http://www.pandora.com/check your phones app store for this one it's really cool.