Try the autoplay feature to listen to a playlist for hours of viewing or hearing.
This website has all the top artists or most of them listed. You login using your Gmail, Twitter or Facebook login and simply
listen to any playlist you want or create your own. Also has a recommended playlist option.
3) Yahoo Music
Custom URL for your personal playlist.
Tremendous variety of music artists and songs.
You can also embed the playlist on your blog/ website allowing it to autoplay- a really neat feature.
Lack of Customization as regards to recommended songs and incomplete integration with Facebook /Social Logins
Custom algol that is very good in creating an automatic playlist based on music you are listening. ( I hole Youtube and Yahoo music have this feature soon)
Some additional features like extensive information on song/artist/album playing.