I wasn't certain if you were aware of this, but I have implemented a Social Sharing function for threads.
There is a small section under the navigation bar while viewing threads, which you can use to share and like on Facebook, tweet to Twitter, +1 for Google+, etc.
I just wanted to ensure you were already aware in case you wanted extra things to add to the board's Facebook, Twitter and Google+ accounts. That way people who visit the pages wont think they are inactive.
I have also implemented them for the Homepage under articles as well.