OK then, with ARM's optimized ASM CPU cores and such, how come they're not holding up against x86 like they used to? I'm ALWAYS interested in nuts and bolts, pipelines and instruction caches, but that's all academic in this case. There's benchmark data which suggests ARM might be in for a competition.
Craig is talking about the quality of emulator code. Where have you seen a comparison between an Atom and an ARM core on emulation performance? Bear in mind, I don't agree with his post at all, I'm just looking at the current situation.
The benchmark data you're referring to is SPEC2k numbers provided by Intel. When Intel submits SPEC numbers on behalf of their competition it's a pretty safe bet that it's not a totally fair test. They've done this in the best with AMD where they totally crippled them. There are a lot of ways you can sabotage a SPEC score. Not just with compiler and compiler settings but also runtime libraries, OS, etc..
Intel probably compiled SPEC for Atom with ICC, and for ARM with GCC (possibly an old version!). ICC often does produce better code than x86 GCC, but on ARM other compilers (like ARM's compiler) have often produced better code than ARM GCC. armcc isn't used that much, but suffice it to say, neither is ICC - not that widely used on Windows and you will especially not see people using it to compile NDK fat binaries on Android.
On the flip side, Atom doesn't win on Phoronix benchmarks vs Cortex-A9 boards, where the same compiler is used and the compiler options are known. And on Android benchmarks, shitty as they are, Atom only wins on Sunspider (and has advantages on Javascript in general) which is an awful benchmark run on engines that probably output better quality code for x86, along with a lot of other relatively artificial reasons for it to be ahead.
Bottom line, never ever put faith in benchmarking numbers used for marketing purposes to make a processor look good. Especially if they don't provide any details on how they did the test much less allow for any kind of third party reproduction. Of course since SPEC2k is an ancient benchmark they have no avenue to even submit the results officially.