StumbleUpon, the video referral site where registered users recommend videos to others, has grown to 5 million registered users who "stumble." or recommend, some 350 million Web pages per month, Garrett Camp, co-founder, told Beet.TV in this interview.   

The San Francisco-based was purchased by eBay last year, but operates independently. 

The company recently expanded the video sharing sites it curates.  The company hopes to add soon, Garrett told us.  I just spoke with CEO Mike Hudack who told me he is quite enthusiastic about the prospect.

Garrett shares his vision for the emergence of contextual video advertising on the site.  And, he gives some good pointers for producers on how to make videos more likely to be shared or "stumbled."  Check this out.

— Andy Plesser

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