Great Resources for GC's on Social Media Policies

In an earlier post, I discussed the need for General Counsel to consider the need for corporate social media policies.  I've just found some terrific resources.  Several websites collect and track the on-line social media policies of various companies, including:

In addition to the policies themselves, each of those sites have links to other sites with useful information, including guidance on how to draft policies.  (I'd hate to be the one tasked with reviewing each and every policy and trying to create a "best of breed" from the group.  That could take the rest of your life, and would probably be pretty bad and out-of-date to boot.)