XSDVCD (If there is such a thing)
MP3 (including VBR) (any accepted media) (ID3 tags display)
OGG (including VBR) (any accepted media)
WMA (any accepted media)
ability to upgrade to allow more formats
Standard 5" and 'mini' (3"?) versions of above.
Manual region switch with ("Zone-switching",All,0,1,2,3,4,5,6,7,8)
Ability to disable 'forced' subtitles
Permits skipping of 'forced' video (warnings, forced commercials, etc)
Plays NTSC and PAL discs, can output either as NTSC or PAL
Other thiongs if I think of them.