You are quite a drama queen :). Windows 8 applications can still be programmed in .NET languages. Given that probably 80% of the application is not 'front-end' code, it can be compiled without changes. On the front-end you can still use whatever was used before, since the desktop still exists. And if you want to go all-'Metro': there is a learning curve, but it is not that steep, since Windows 8 applications are also developed using XAML et al.

Disclaimer: as a OS X and Linux user, I don't know much about Windows.