Only days after hip-hop band Public Enemy threw its weight behind the new audio compression technology (CI No 3,575), Australian internet service provider OzEmail Ltd has adopted Global Media Online (GMO)’s controversial MP4 format for its online music channel, CMM. MP4 files are three to four megabytes in size, and can display scrolling text messages, album cover art and hyperlinks to an online store where listeners can buy the sampled product. The big attraction for content providers is that the format doesn’t need a player installed; the song files are self-playing. In spite of its name, however, MP4 is GMO’s own proprietary format, and is not to be confused with the Motion Picture Experts Group MPEG-4, the true successor to MP3. That hasn’t prevented artists from Public Enemy to Australian band This Is Serious Mum from releasing tracks in MP4 to express their support for the format and for OzEmail’s launch.