Copied from the most recent dw_news entry:

"A recent code push made it possible for [Dreamwidth] to define 'safe embedding sites' -- sites for which the < embed > tag will work and not be cleaned out. We need to specifically whitelist these sites because the embed tag has the potential to introduce Very Nasty Stuff, risking the security of your journal and the journals of anyone who views your journal.

So, we thought we'd poll you for 'safe' embedding sites that you'd want to use. Obviously, YouTube is on the top of the list, and people have also requested Vimeo, but what else should be allowed?"

So far in comments people have requested and/or seconded:

blip.tv
Dotsub
Flickr
Vimeo
The National Film Board of Canada
Current TV
Viddler
Comedy Central
Hulu
Dailymotion
widgets from Plurk
videos from Nico Nico Douga (Japan's Youtube)

Comment over there to add your own suggestions or second (or third!) the already listed services.