The PTO has published statistics relating to the new AIA procedures of Inter Partes Review, Covered Business Method Review, Post-Grant Review, and Derivation Proceedings. You can access the statistics here: [Link]. It is interesting that one post-grant review petition has already been filed. A post-grant review must be directed against a patent that was filed after March 15, 2013. My understanding is that the particular patent at issue is a design patent. Also noteworthy is that at least one derivation petition has already been filed.