I find Pandora's service to be exactly what I am looking for. I love the fact that you can add songs or artists to any station if the music starts to get repetitive. I use Pandora all the time and my only thing against it is that you have to pay if you go over 40 hours but really I don't mind supporting this service.
I would recommend Pandora to anyone who wants to listen to music for free without having to manage a playlist or if you want to find new artists in a genre of music you like.
Glad we could help!