It has only been one month since Facebook officially launched Facebook Connect. On December 4th, the social network decided to allow its users to carry their credentials and their community of friends with them across the web. Already having an immensely popular platform for developers to build applications, Facebook has now seen hundreds of sites adopt Facebook Connect to allow users to log in, share information with friends, and report some of this activity back to Facebook.

Interestingly, two of the most trafficked Facebook Connect integrations to date are from video sites Joost (at 18,500 MAU) and Vimeo (7,500 MAU). (Hulu has announced Facebook Connect support, but has not yet launched it. YouTube, which is owned by Google, is unlikely to implement Facebook Connectin the near future.)

While these numbers may seem small in comparison to many on-Facebook apps, Facebook Connect’s adoption on video sites shows that many users are choosing Facebook Connect to more easily login and share videos with friends.

Using Facebook’s technology, these video sharing communities will grow more quickly. What is not yet certain is how much of these video sites’ traffic will come through sharing on Facebook in the future. Media companies are always concerned with growing their audience as much as possible — though Facebook Connect, could Facebook replace Digg and other social sharing sites as the top traffic referrer?

It will be interesting to see how Facebook Connect grows, especially in video sharing sites (and blogs) which already have a focus on building communities.