Check out Chill.com, the Turntable.fm of watching videos online with other people. The set-up is basically the same as Turntable.fm, but instead of somebody playing a song, they play a video. There already exist other services that allow you to do this, like Google Hangouts, but Chill makes it more fun and easier.
The service will search YouTube, Vimeo, and Hulu to find the video you are searching for.
Everything else is pretty similar to Turntable.fm. If you have Facebook friends using Chill already, you can sign up. Note: After a disagreement with Facebook’s Mark Zuckerberg about the service auto-posting a pro-Chill message to people’s accounts, they have limited the number of new signups currently allowed.