I'm a Nerd, Are you a Nerd?

Yesterday when I checked-in on Foursquare for our library I was awarded a Bookworm Badge and called a nerd.  According to Joe Murphy on his blog this is a new feature of Foursquare.  I had just thought that they were trying to tell me something in a not so subtle way.  One might forgive me for making that assumption as I have been accused of nerdom a time or two before.  Ok, maybe three.  I had also thought myself as nothing short of brilliant as I had left a tip promoting the Overdrive app to check out and use library ebooks and audio books on iPhone and Android phones.  Turns out I am not the only clever one.  Joe suggested using Foursquare to promote library programs and to award users for becoming mayor.  I like the way he thinks!  My only question is how to coordinate this in a large library system of which we are but a humble part.  Since Foursquare is a location based app, it would seem to make sense for each library in the system to go about this individually with occasional coordination for the central office.  Something to ponder.  How do you use Foursquare in your library?