Slowly, academic papers are emerging on the MapReduce model: here is a list of recent papers from bio to GPUs, decision trees and beyond, and a system-sy bib. We are still far from developing a theory of algorithms for it, but some good examples are emerging. In WWW 2010, Flavio Chierichetti, Ravi Kumar and Andrew Tomkins had this paper Max-Cover in Map-Reduce which is a quintessential algorithms paper in MapReduce model, enjoy! For a puzzle, consider solving the prefix sums problem. How many rounds do you need in MapReduce?