[Windows 8 General] SixSixSevenSeven:
I'm with mcosmin222, your post makes no sense. Being ARMv8 means that there is no downside to being 64 bit? The hell are you smoking, decreased 32 bit performance and double RAM usage for 64 bit software on a device still using the same 1gb of RAM as its 32 bit predecessor, MAJOR downside.

Also for most developers there is no extra maintenance for 64 bit and 32 bit OSes. Seriously, most of the time its as simply as changing one setting when building, sometimes more effort is required but usually less than is required to simultaneously support iPad and iPhone in an iOS app (they dont scale well automatically all the time which is why on windows systems and my brief android foray I design with variable screen sizes in mind). Drivers are an issue yes, but most developers are not driver developers, even then 32 bit windows user mode drivers work fine in 64 bit windows, its only kernel mode drivers which require native 32 vs 64 changes.

Slight hypocrisy there.

It is debated by some whether the atom is a SoC at all, intel do not claim it to be with the exception of a few models which do indeed have more peripherals built into the chip itself than their counterparts, my view is that they are increasingly moving towards a SoC design with the only major external components now being the RAM and storage (of which the typical SoC usually has RAM and sometimes storage internally). There is not a single intel core series processor which is a SoC.

32 bit windows with more than 4gb of RAM I find hilarious, I bought a second hand PC running windows XP 32 bit on 12gb of RAM.... Loaded my copy of windows 7 64 bit onto it immediately. Quite a few people dont seem to realise that the 4gb ram limit also counts video ram too.

I dont know about core count difference for x86_32 vs x86_64. I saw intel demo'ed a prototype 80 core - single CPU (x86 systems can distinguish between having 2 dual core CPU's on one motherboard and 1 quad core CPU) using intel atom 32 bit cores. In the consumer electronics market, 80 cores would be unheard of. Even the server market probably doesn't go beyond 80 very often. Super computers dont always use x86 but may well hit the core limit if there is one :P

The one place where your suggestion of using visual studio to show 64 bit vs 32 bit differences would really show the advantage of 64 bit is when your software uses a long rather than an int. Int is a 32 bit number. Long is 64 bit. 32 bit processor can't handle longs natively so has to have additional software overhead for longs. Compile for a 64 bit processor and you can use a long instead. Float vs Double I have heard people saying makes a difference but I believe most compilers simply use the x87 math processor embedded within all x86 chips which I think handles doubles natively on both 32 bit and 64 bit x86 processors.

I dislike apple, but I have found one place which justifies the double performance claims. They claimed double performance for the entire SoC as a whole not just the CPU. ARM NEON has had a performance bump in ARMv8. The A7 chip also has an upgraded GPU over the A6X (PowerVR quad core still though so hardly cutting edge). There is also the matter of which benchmarks they use and whether the benchmark does use any 64 bit math. Benchmarks are of course not always indicative of real world performance and for the most part you will *not* see a difference on the iPhone 5S.