Originally Posted by CarlosTheGaucho

I used to submit some, and found great differences, not only in CTR but also in the traffic productivity for the same clips / landers etc.

Some are just not worth the hassle and keep in mind the only proper way to do this would be to give you a part of the revenue the videos generate with the ads once the video is played.

Say if you get 1 sign up for 50 000 video views and even if you make $ 50 avg. per join, you still just made 50 000 + impressions for all the ads around your video. One should establish and keep a similar metrics in mind when measuring productivity.

Otherwise, even if you factor in the occasional type in joins you simply give out content to somebody else to profit from and get no returns. Although some tubes dominate search results and get a sheer volume this doesn't make their traffic in combinatoin with your clips / site productive.

If somebody looks for your content on tubes at least make sure they find it on the tube that performs the best.

Also be careful about the licensing terms / embedding / downloads etc. not to be surprised.

Anyway to the questions:

1) yes there is one site that, based on experience, outperformed all the others, can share via email / IM
2) testing will determine this, however no matter what length I'd go for a good edit with enough branding, in high video quality
3) good video quality will make your content stand out as opposed to all the older, lesser quality stuff and make people search for more and return to it

Based on experience it's the good, not bad experience on tube that eventually makes somebody sign up for your site. It's bookmarkers or those that return and have good experience on site that are more likely to return to your content, some of which may eventually buy.