While d7o3g4q released the first public (closed source) 'proof of concept' media player for the Xbox (which was called XBPlayer), RUNTiME released the second working media player for the Xbox. RUNTiME's player was called XboxMediaPlayer (which when shortened is called XBMP). RUNTiME and d7o3g4q soon joined forces and adopted XboxMediaPlayer as the name as they started to develop that player as a joint effort. A couple of month after a third (open source player) from a developer called Frodo was release under the name YAMP (Yet Another Multimedia Player). Another couple of months later Frodo joined d7o3g4q and RUNTiME in the XboxMediaPlayer project and XboxMediaPlayer was made open sourced. A couple of years later the XBMP project team-members announced XBMC (XBox Media Center) as the successor to XBMP. XBMC is a complete rewrite of XBMP by the same developer-team, ...and the rest is history.
RUNTiME has retired from the XBMC project and has instead recently founded Transcode 360 (a partialy open source on-the-fly and real-time audio/video transcoder which makes it possible to stream unsupported video over Xbox360 and other Media Center Extender devices).