I am on Facebook!
I am using LinkedIn for last 2+ years and also pay $20/month for the advanced features. Now i am also starting to use Facebook.
I don't think i can keep myself updated in both networks and sometime in the (near) future, may have to focus on only one... Right now, i have lot's of contacts in LinkedIn and less contacts in Facebook.
For now, i see there is a value in keep using (& paying?) LinkedIn and revisit some time in the future to discontinue one....
Is the Facebook is the Google of SN? It looks like...
-Uday.