Reference needed for Iron-based superconductors Iron-based superconductor is a class of high-$T_c$ superconductors discovered in 2008.
Are there any review papers about these superconductors yet? If not, which are the key papers in the field?
 A: Well, Let Me Google That For You
For specific recommendations, the review in Nature by Paglione and Greene1 is very highly cited and accessible.  There is a review of the magnetic properties by Lumsden and Christianson2 and a somewhat older article is available from Hosono and collaborators3.   A Nature review on the debate over the pairing mechanism is available from Mazin4.

1 J. Paglione & R. L. Greene, "High-temperature superconductivity in iron-based materials", Nat. Phys. 6, 645-658 (2010), arXiv:1006.4618.
2 M. D. Lumsden & A. D. Christianson, "Magnetism in Fe-based superconductors", J. Phys.: Condens. Matter 22 203203 (2010), arXiv:1004.1969.
3 K. Ishida, Y. Nakai, and H. Hosono, "To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report", J. Phys. Soc. Jpn. 78 (2009) 062001.
4 I. I. Mazin, "Superconductivity gets an iron boost", Nature 464, 183–186 (2010).
A: 10.1103/RevModPhys.83.1589: A comprehensive review in Dec 2011 by G. R. Stewart containing a myriad of key experimental and theoretical results. Preprint available  at arXiv:1106.1618.
