We all know that the cuprate superconductors continue to give condensed matter physicists fits even more than 20 years after its discovery. Now the iron-based superconductors look like another candidate to provide a lot of delicious puzzles for experimentalists and theorists alike to ponder upon for many years to come.
This wonderful article provides a comprehensive review of the progress in our understanding of the nature of superconductivity in this family of material since its discovery in January of 2008. Other than the topological insulator, the iron-based superconductor could be the hottest topic in condensed matter physics at this moment. The best part about it is that, the story is still unfolding, but at such a rapid rate. It seems as if almost every month (week?) that we see astonishing new results that boggle the mind. For physicists, this is what we became scientists for.