mechbunny if you have the cash, my script if you want something that'll scale but doesn't have quite as many community tools as something like youtube but it has user uploads, comments and all the essentials at only $40
vidiscript seems to be the best free option out there.
if you're looking at running the illegal tube setups Nubiles, STXT and TEVS really are not options. Those are mainly centered around sponsored videos.
There is a REALLY nice tube system around $200
http://www.mediascripts.com/social_features.html honestly thats probably your best bet, it has far more features compared to well ANYTHING out there.