I think my library does quite a bit for social media. Their facebook page is my favorite. They have a weekly passive program called book talk tonight. Basically a librarian gets on Facebook and chats with everybody about what they are currently reading and enjoying.
I also found out that my library has a pinterest which they post quite a bit on and a twitter account.
I haven't finished any books since my pile last week, but I have been to the library twice so I have now have a huge pile of books that I'm working through. From top to bottom they are Little City by the Lake by Cecila Wilkins, The Rules for Disappearing by Ashley Easton, The Frog Princess by E.D. Baker, Clockwork Angel by Cassandra Clare, Tener Morsels by Margo Langan, The One and Only by Emily Giffin, City of Heavenly Fire by Cassandra Clare, and The Little House in the Ozarks by Laura Ingalls Wilder.
I'm hoping to accomplish a few of these books this week.