A leaked beta version of iOS 6 reveals hardware details of the next generation iPhone, according to 9to5Mac.
The iPhone running iOS 6 boasts Darwin Kernel Version 13.0.0. We can also see that the processor is an ARM S5L8950X.
Darwin Kernel Version 13.0.0: XXX May XX XX:XX:XX PDT 2012; root:xnu-21XX.X.XXX/DEVELOPMENT_ARM_S5L8950X
Interestingly, that is a full release above the most current developer version of MAC OS 10.8 Mountain Lion. The XNU build is also higher (21XX vs 2050.5.8):
Darwin Kernel Version 12.0.0: Tue May 8 17:30:17 PDT 2012; root:xnu-2050.5.8~1/RELEASE_X86_64 x86_64
The Samsung 5L8950X ARM processor is a step up from the S5L8940X on the iPhone 4 and the S5L8945X on the new iPad but further details are unclear. It's known as the "A5-***" internally (the last three characters were removed to protect their source). It's not likely the final name but does suggest that the the next iPhone's processor will still be a A5 processor rather than stepping up to A6; although, that is still uncertain.
The next phone will reportedly get a new GPU chip called the "SGX543RC*" (the asterisk is another sensitive number that could identify people working on the device). It will reportedly continue to have 1GB of RAM.
Notably, the device used by their source features the same Qualcomm baseband found in the iPad 3 4G but this is expected to change.
"Our source indicated this might be because he/she does not need access to any new baseband that they might use. Moreover, the battery life is not a concern, because this unit must always stay plugged-in. We expect the final N41AP / iPhone5,1 to carry the latest Gobi chips. These chips should allow low-power voice/data on a variety of mobile networks, including China Mobile's TD-LTE."