The joint meetings of the AMS and MAA are going on right now, and among the prizes being awarded is the Levi L. Conant Prize for the best expository article in the Notices or the Bulletin of the AMS in the last 5 years. One of the two awardees is the group consisting of Shlomo Hoory, Nati Linial and Avi Wigderson, for their article 'Expander graphs and their applications' in the Bulletin of the AMS (here's the related course).
Congratulations ! On a side note, I'm truly impressed by the number of prizes awarded for articles that are expository or targeted at the general public. I don't think that the mere creation of prizes encourages people to write such articles; rather, the existence of such prizes is a post facto demonstration of the intrinsic value attributed to exposition in the mathematics community.