Sorry, this is a bit late, but I've just tested this on my Nokia N800 with OS2008

Call was made from N800 to PC. PC video came over fine, but the video stream from the N800 came up pretty pixelated, even over my local WiFi network. This was tested with desktop PC and N800 using the same access point in the same room.

It works, but the video needs a bit of tweaking. I can test this with the N800 connected via HSDPA to my mobile network if anyone's keen to know how the video is going to turn up over the mobile data network.