Raspberry Pi SoC consists of two parts: ARM and GPU(VideoCore). Most of the interesting stuff like OpenGL, video playback, HDMI controls are implemented on VideoCore side and can be accessed from OS through libraries provided by Broadcom (userland repo). These libraries were ported to FreeBSD some time ago so Mikaël created port misc/raspberrypi-userland for it. He also created port for omxplayer (low-level video player that utilizes VideCore APIs) and is working on port for Kodi (ex-XBMC) - more user-firendly media player software with Raspberry Pi support.