1. RIP __rdio__, nothing has ever replaced the amount of music I discovered using this service (at least from an automated perspective).
The "radio station" functionality has been great for me. I do most of my music listening while on the motorcycle, and it's easy to thumb things up and kick off new radio stations via voice commands. So I've been able to meander through various musics and have had a pretty continuous stream of artists I wouldn't have heard of.
One of my favorite things about Rdio was the ability to have multiple radio stations and your likes / dislikes would only affect that station. So if I'm trying to make a 60s rock station and a Johnny Cash song comes up, me disliking Johnny Cash on that station wouldn't affect my classic country station where I definitely want to hear Johnny Cash. Such a neat feature...and it really helped with discovery IMHO.