I haven't been real hot on internet radio because of the programming. They either have "all the hits" or extremely obscure, but nothing in between. I went ahead and accepted the invitation to Spotify, and I am excited. If the radio show I accepted is not set up to loop, I'll probably have Spotify on 24/7. I picked the 60's and have heard Spirit, Sly And The Family Stone, Art Blakely, Grateful Dead, Dionne Warwick, Tony Williams, Rhinocerous, Charles Mingus, Pete Seeger, Mies Davis and much much more - all great songs, but none were the "top hits", which means I'm enjoying familiar flavors, but not overly familiar. I love this type of listening because my ear stays tuned better. The overly familiar "hits" tend to make my mind wander.
Based on a few hours of joy, I will very highly recommend Spotify. They have radio stations for all eras, so take your pick and try it out.