We now have a new "tag" built in to the site that allows the posting of media files. Here is an example of what it can do:

[MEDIA]http://www.youtube.com/watch?v=z4ZnpLM3ldc[/MEDIA]

To use it just click the blue "M" button on the editor toolbar. Then input the URL of the file between the "media" tags. For YouTube you would just copy the URL of the page for the video and place that between the "media" tags. The supported flash video sites are:

Google (http://video.google.com/)
Youtube (http://www.youtube.com/)
vSocial (http://www.vsocial.com/)
iFilm (http://www.ifilm.com/)
MetaCafe (http://www.metacafe.com/)
DailyMotion (http://www.dailymotion.com/video/)
CurrentTV (http://www.current.tv/studio/)
Vimeo (http://www.vimeo.com/)
Sharkle (http://www.sharkle.com/video/)
FreeVideoBlog (http://video.freevideoblog.com/)
MyVideoDe (http://www.myvideo.de/)

It also supports these file types:

Adobe Flash:
swf, spl, flv

Quick Time:
mov, qt, mqv, mpeg, mpg, m1s, m1v, m1a, m75, m15, mp2, mpm, mpv, mpa, flc, fli, cel, rtsp, rts, 3gp, 3gpp, 3g2, 3gp2, sdv, amc, mp4, sdp

Real Media:
rm, rmvb, ra, rv, ram, smil

Windows Media:
mp3, wma, wav, ogg, ape, mid, midi, asf, asx, wm, wmv, wsx, wax, wvx, avi

Adobe PDF:
pdf, fdf, xfdf, xdp, xfd

Image File:
gif, jpg, jpeg, bmp, png, xpm

P2P File:
torrent, emule, foxy, pplive