What are the chances that the iPad will have the world's first production ARM A15-based SoC, instead of an A9-based SoC? (I'm not talking about Apply A5 / A6 nomenclature, rather the underlying microarchitecture).
There is supposed to a really large improvement in quad core A15 performance, clock for clock over quad core A9, mainly because of improved bandwidth, but also because of other contributors to improved IPC (instructions per clock) such as larger caches, better branch prediction, out of order execution, etc.
If the iPad3 is still A9 based, then we know where they will go for the iPad 4 (or whatever the iPad for 2013 is called).