Сколько физических процессоров поддерживает Windows 8?

Since you're talking about the max. physical (not logical) processors supported, I can say that the numbers for Windows 8 Core (1) and Pro (2) are most likely correct. I'm sure this sort of limitation is for the client versions of Microsoft's OS only, and not the server versions.

As for official documents, other than the About.com page that mwong mentioned (with no sources listed, which Thurrott also omits), I have so far not found any technical documents regarding the limitation (all I could find were older ones related to Windows 7). What I did find however were legal documents that specify the number of physical processors the two versions are licensed to run on, so most likely the code enforces the legal limit as well.

What are these legal documents? They are the EULAs we all ignore while installing Windows. If you don't want to bother running Setup to confirm, you can download PDF copies here.

Windows 8 (Core) Software License Agreement

Windows 8 Pro Software License Agreement

The EULA for Windows RT does not seem to explicitly mention the number of physical processors supported. Windows Server (2012) versions are licensed depending on the number of processors installed (each license = 2 physical processors, so no. of licenses required = ceil(no. of physical processors installed / 2)).

According to some quick research:

"Windows 8 Pro supports a maximum of 2 physical CPUs and the standard version of Windows 8 just one. In total, up to 32 logical processors are supported in 32-bit versions of Windows 8, while up to 256 logical processors are supported in 64-bit versions."

Source: http://pcsupport.about.com/od/windows-8/a/windows-8.htm

TL;DR: Pro supports 2 and standard supports 1.

That screenshot came from a MSDN blog, from an early development build of Windows 8. I'm willing to bet that that version was not capped at two physical CPUs (note that this is an artificial cap to force purchase of Windows Server, and prevent use of home licences for hosting a commercial server), and that they just wanted to show off how many logical processors the Task Manager could handle gracefully.

I guess Windows Server would find this feature more useful; however I have never used it so I cannot be sure.

The figures in your chart look right to me. Home/PC versions of Windows have been capped at two as far as I can remember. There was a licence somewhere on the MS site that said one, but I guess that meant the non-Pro version.

Насколько я понимаю, лицензирование Microsoft распространяется только на пакет физических процессоров, поэтому, например, в Windows 8 Pro вы можете использовать 2 ядерных процессора 8 (например, Intel Xeon E5-2680, S2011, Sandy Bridge, 8 Core в двухпроцессорная материнская плата), дающая пользователю 16 реальных процессоров и при этом не нарушающая лицензии.