According to ars technica:
This is not good for open source. I doubt Microsoft will ever put forth effort for full C++11 support in VS 2010. So, this essentially means that, if you want to compile not only traditional Win32 applications but also standard C++11 code on Windows, you’ll have to pay for the professional version of Visual Studio.
Photo illustration by Aurich Lawson
Update (June 9, 2012):
Apparently, Microsoft has changed it’s mind. Good.