Vividas is enabling full-screen online videos. The company sells software, but you can view a demo without downloading anything. Here’s a beautiful Ford ad that works very well in full screen. Click the link and you’ll need to authorize a pop-up. It took my Mac a minute for the video to cache but it was worth it. (Via Patrick). Here’s another site that never loaded for me, but may for you: FlashBeer.
Vividas makes software that publishers use to distribute the video, but viewers don’t need to do anything except authorize a pop-up. That’s probably the company’s biggest challenge. Initially that requirement would freak me out if I received a video from a non reliable source.

That said, the world of television and web are moving closer by the minute.