I'm a C#, C++ & Java developer, and have seen both sides of the fence dividing Developerville for over 14 years.
This is why I think MS will get developer support:
1. Tools - they have well integrated tools, which are free to use.
Nothing out there can match the ease of building an app for desktop and mobile with Visual Studio. Google has done an impressive job with the Android development tools & tutorials, but Java based desktop apps are an entirely different story with FOSS alternatives like the do-it-all Eclipse framework which are not easy to get productive with.
Though I am peeved to see Windows Phone 8 development needs Windows 8 and SLAT processor support, which means I would need to replace my "old" laptop which runs Windows 7 & the Windows Phone emulator just fine, to do Windows Phone 8 development.
2. Consistent managed programming languages between desktop & mobile.
I quite like how MS has extended Silverlight's C# / XAML paradigm to both desktop & phone. C# is easy to learn and C++ is a first class language on Windows 8 desktop and phone. While C++ is difficult for novice developers, good C++ devs will continue to be in demand for efficient LOB apps, and I can see them migrating to this paradigm.
3. C# & XAML are easy to learn.
From a business perspective, platform integration implies skill reuse and reduced headcount. From a business perspective, cost is also important, and MS may have shot itself in the foot on the pricing of its Windows 8 tablets.
Will the desktop equation change if the "Mother Of All Walled Gardens", Apple, reduces Mac desktop prices?
Just my 0.02.