Best streaming music site: GrooveShark

My criteria for a streaming music site are simple:

1. An account is NOT required in order to use
   
2. No limit on the number of times you can listen to a song
3. The ability to listen to full songs, not just clips
   
4. Comprehensive collection of songs
   
5. Ease of use in playing the song you want
6. High quality audio
   

GrooveShark is the best for all of these. It meets all of the criteria, and does so quite well. It also allows you to embed songs and playlists on other web pages/blog posts (although the process for doing this is quite obtuse). I also really like how GrooveShark does a pretty good job of de-duping search results. Other sites will list multiple versions of a song of varying length and quality.

Runners up include PlayList and YouTube. PlayList isn't as comprehensive, and doesn't de-dupe, and YouTube has low quality audio. Sites that don't meet my basic criteria include Rhapsody, MySpace, iTunes, and Amazon MP3.