Anand thinks the processor in the iPhone 5 (Apple A6 SoC) is a custom processor. I'm looking at whether the evidence for this. I don't know what Apple have done but I do understand some of their options.
We have information (from Apple) that the A6 processing power is up to 2x faster than the A5. Anand also has the "some information" that it is not using Cortex A9. The is also clue in Xcode that A6 supports "ARMv7s", although there seems to be no easily accessible public definition of ARMv7s.
So, let's look at ARMv7s.
Could ARM7s be just VFPv4? As I understand it, VFPv4 (just) adds fused multiply-and-add and the half-precision extension to the instruction set. The number of double word registers used in VFPv3 and VFPv4 can be either 16 or 32 (16D or 32D). In terms of ARM's processors Cortex A9 implements VFPv3-D16, and Cortex A15 implements VFPv4-D32 - as can Cortex A7 (Anand seems to have this wrong).
It is conceivable that ARM7s means VFPv4-D32 although I would have expected there were other ways of indicating this combination. [I'm less worried about not representing the Cortex A15, Cortext A7 and Qualcomm Krait's support of Large Physical Addresses and Virtualisation as these shouldn't affect compilation].
Then, given Apple A6 has an ARMv7s processor it isn't Cortex A9 based. So what is it?
The licencable ARM processors that been available for long enough to allow Apple to launch now are the Cortex A15 and the Cortex A7. At identical clock frequencies Cortex A15 is about 1.4x faster than Cortex A9 (Dhrystone). Accordingly 2x performance can be reached from a 1.4x increase in clock, from 800 MHz to 1.12 GHz - not high compared to the quoted figures of other smart phones. There are rumoured power consumption issues with high-frqeuency Cortex A15s but there are things that can be done to deal with this. [For example, ST-Ericsson has chosen to use advanced manufacturing process technology (FDSOI) (see this and this), and ARM themselves promote "big-LITTLE" technology]. So, I'd count dual-Cortex A15 as possible.
What does this leave in Anan's analysis? Just the "I've confirmed that Apple's A6 SoC is based on Apple's own ARM based CPU core" - nothing technical.