Is this about language or about control?
I think the whole thing runs much deeper than most people care to realize.
First of all; the whole suggestion of a "post .NET world" is preposterous. Because what exactly is WinRT? Basically its a set of Windows 8 APIs, just like the current API ("Windows API" also called "Win32 API") is available on Windows 7 and Vista. Also from .NET, so what's the issue here?
But the reason I call this preposterous is not so much because of the obvious above. Has the author already forgotten about Windows Server 2012? By default this installs in a 'core mode' thus leaving only a command line based console. Administration is done through the Remote Server Administration Tools ("RSAT") and/or... Windows PowerShell. This is Microsoft's "new" de-facto administration tool. And guess what; it sits completely on the .NET framework. PowerShell is what eventually got me to grab a version of the Express versions of Visual Studio for VB.NET and C#.NET.
I think language access is the least bit to be concerned about. When it comes to the influence of the new TIFKAM environment I have much bigger concerns: An immense decrease in control. On Windows 7 I can basically install and use whatever I want. On a TIFKAM based environment I can only use whatever Microsoft provides me with in their marketplace. Thus effectively generating an environment for them to rule out any players which they don't like.
Office 8 is fully TIFKAM integrated. Do you really think that should the OpenOffice people ever step onto the TIFKAM bandwagon and produce a TIFKAM enabled version of their Office environment, that it would find its way onto the Microsoft marketplace? I sincerely doubt that.
THAT is in my opinion the real danger of the whole Windows 8 doctrine. Its not a change of development, its not so much an issue of being forced onto a touch-based user interface which should also be pushed down the throats of the desktop users. No, in my opinion this runs much deeper and seems to be more sinister ("seems to be" because at this point I can obviously not state that MS would actually ban programs such as OpenOffice, but they do create the environment which would allow them to).
Don't worry about languages, worry about being forced into a Microsoft dominated and controlled environment instead. Please note that I'm not suggesting that such an environment would be "bad" or "evil" perse, not my words. But I do state that such an environment could easily be (ab)used to do exactly that.