Originally Posted By: Roger
There's also the problem that the PS3 originally had a limited set of supported formats. This has probably improved with later firmware updates, but who knows?

Anything MPEG (1,2,4) including H.264/AVC for audio and video should work out of the box with any firmware version. Full Divx support was also added in recent updates, including the early Divx 3 support. Also, WMV should play, but I'm not sure exactly what versions as I tend to avoid keeping anything in a proprietary MS video or audio format.