In a move that will heat up the battle in the online music, imeem acquired today Anywhere.FM, a San Francisco-based web music player and Internet radio service.

Imeem’s move follows after last week Last.Fm has signed distributions deals to offer to its users free, global, on-demand access the music catalogs with all four major record labels - including Universal Music Group, Sony/BMG, Warner and EMI.

Launched in 2004, Imeem is the fastest-growing social networking Web site, according to comScore data. More than 50,000 new users in the age 24 or younger join the site every day. It is the fourth most popular multimedia entertainment site in the U.S. after Google Inc’s YouTube, Google Video and News Corp’s MySpace Videos, according to tracking firm Hitwise.

Imeem has also distribution deals with all the four major music studios.

The last music studio that signed a deal with imeem is Universal Music. In December last year, imeem that in addition to receiving a fraction of the advertising revenue that is associated with certain songs, Universal will receive a guaranteed payment each time a user listens to one of their songs.

For example, the Anywhere.FM desktop uploader enables users to quickly and easily upload their personal MP3 collections to the Web and stream their favorite artists, songs and playlists from any browser. Besides the uploading options, imeem will be able to offer to its users some very interesting features.

Anywhere.FM will bring to imeem its recommendation engine and its sophisticated “Friend Radio” feature that lets users discover new music by streaming playlists their friends and other users have uploaded

The financial terms of the deal between imeem and Anywhere.Fm were not disclosed.