This is a 50 min. talk/presentation by Jawed Karim – one of the three YouTube co-founders – about how and why (social networking) sites like YouTube became so popular in the last couple of years. Although it focuses on the bigger known services this is very interesting to watch. Specially towards the end (last 10 min. or so) there is a lot to learn about why YouTube works/what made it work – recommended for anyone who has to do with social networking sites or wants to better understand them…