With new social media tools sprouting up weekly, it's tempting to dismiss many of those that pass through but when I saw the Libraries and Information Science Stack Exchange come through late this spring, I was intrigued. The Stack Exchange is a network of Q&A sites meant to help answer questions from given niches with the help of experts in each field. The beta for the Libraries and Information Science site has garnered over 200 questions (and nearly 700 answers!) from 600 librarians in our field. The site says that public betas typically last from 60 to 90 days but based on the engagement, I'd be surprised if the site doesn't become a "full member."
The site is similar to other Q&A sites, but with a few bonus features. The posts can be rated by their usefulness and moderators garner badges which describe their engagement. For instance, the "enlightend" badge is assigned to someone who was the first to answer and whose answer was accepted with at least 10 upvotes. The site also appears to be mostly free of spam and troll comments.
I encourage you to take a look, answer some of the questions and pose those burning to be asked!