with the following exe you can try them out! :D

first save attached water.mp4 to C:EJukeboximagesyourskin

then add the following to the top of colors.ini and save
[IEStandardsMode]
Version=9

[VideoBackgrounds]
Enable=True
NowPlaying=
PlayList=
ArtistList=water.mp4
SongList=
AlbumList=water.mp4
HomeView=water.mp4

Tools->Skin->Reload skin to see the video backgrounds. Vista/Win7 with IE9 required.

note: using the same filename.mp4 saves resources so does using ?=
it is supposed to accept all mp4's encoded in h.264 but some don't work ...still trying to find a reliable encoder for this with the right profile that is compatible for converting any video. if anyone finds the right encoder program and the right settings please share.

EJ now supports the following options in all .DIS and homeview.ini

#BGVideo { opacity: 0.9; }
#OverBGVideo {
display: block; filter:progid:DXImageTransform.Microsoft.gradient(enabled='true',startColorstr=#3366FFFF,endColorstr=#80000099,GradientType=0);
}

there is also now support for a shelfbgvid.dis file containing the above