I have been streaming videos for years, avi,divx wmv formats seem to work the best, as soon as you get into the 720p and higher(especialy mpeg4) there is a serious drop off in delivery , i usually have to convert them to avi to get a smooth stream otherwise the sound gets all choppy, i have tried just about every codec's pack there is, FFdshow seems to works the best for  decompressing DivX, XviD, H.264, FLV1, WMV, MPEG-1 and MPEG-2, MPEG-4 movies. Im really interested to see what becomes available over the next few years, i gotta say, the first time i watched the The mummy-dragon emperor trailer on dutv's website i was hooked, try and watch that same thing on youtube in that quality, lag city, big things coming