In case you missed it, there’s a pretty thorough overview of the online video industry at read/writeweb.
They cover multiple players in Video Sharing, Intermediaries, Video Search, Video eCommerce, Video Editing & Creation, Rich Media Advertising, P2P (Peer To Peer), Video Streaming, Vlogosphere.
I’m sure there are a host of additional companies not listed, but it gives you an idea. The reference to stealth mode startups is very appropriate as well- there’s a lot of activity in this space that’s starting to bubble to the surface.