Wikipedia says this about the site:
Playlist, Inc., operator of the playlist.com website, is a company that provides widgets for MySpace and Facebook. It claims to be a search site for music files and does not store any music on its servers. It does pay royalties to music sites and all content on their site is strictly legal. It lets users of MySpace put more music on their profiles where otherwise they would be only allowed ten.
History
It was founded in the early 2000s for the purpose of putting more music on myspace and other social networking sites which only allowed one song. With the popularity of social networking sites and online blogs playlist.com has experienced enormous growth. From a userbase of less than 500,000 in the mid 2006, now the site boasts more than 20,000,000 users as of June 30, 2008. According to alexa.com, in the United States and Puerto Rico it is one of the top 100 sites. It was originally known as projectplaylist.com, before it acquired its current domain name of playlist.com.
] Legal issues
A key concern for this site was that the majority of the files linked to are pirated content distributed without the authorization of the copyright holders. On April 28, 2008, the RIAA and a coalition of nine record labels filed a lawsuit against the company for contributing to mass copyright infringement.[1] However, it has been noted that two similar cases against MySpace and Imeem were largely the opening moves in settlements which would see these music sites licensing the content and compensating artists for the use of their music. It is possible that playlist.com would wish to pursue a similar strategy.[2] Project Playlist already has begun contracts with Sony BMG.
On December 19, 2008, MySpace quickly began removing the Project Playlist music player from all profiles and subsequently leaving the affected users a message in their inbox which notified them of the removal and that Project Playlist was officially banned from MySpace for the time being, largely due to complaints brought forth by the artists. They stated that unlike MySpace or Imeem or others, Project Playlist did not pay royalties and was thus operating illegally. MySpace, however, assured users that as soon Project Playlist's "legal situation is settled, and the artists are getting paid, MySpace will consider re-enabling the embedding of Project Playlist music players."
[edit] Applications
Music playlist that can be embedded into MySpace, Myyearbook, or Facebook using their application platform. It should be noted that due to Facebook's different format which does not use HTML coding, the player is more obscured and can not be set to auto-start as it would on Myspace.
Social networking -- users get a free profile and have the ability to message each other and add other users as friends.
On December 23, 2008, Facebook followed MySpace's lead of removing the Project Playlist application from their website.
Other social networking sites such as myYearbook have yet to remove playlist.com's widgets.