"First, let’s look at the C++11 language features. Clang 3.3 and above, and GCC 4.8 and later have complete support, so there was no point including them in the table."
Also note that, on the C++14 front, clang supported all language features and most library features. And that is a year ago.
That's kind of like saying "You haven't read Shakespeare until you read him in the original Klingon."
Waiting for Microsoft to make a compiler seems like it ought to be orthogonal to moving the language forward, especially when non-Microsoft tool chains are already doing better with that particular language.
Microsoft has enough on their plate bringing C# and .Net to Linux and Unix, and I'd much rather they get that right than compete with GCC and CLANG. (That and Docker for HyperV and Windows Server.)
But Visual studio doesn't imply Microsoft's C++. There's clang-cl (http://clang.llvm.org/docs/UsersManual.html#clang-cl), which aims to be a drop-in replacement for Microsoft's compiler (haven't used it, so I don't know its quality)
Also, Visual Studio 2015 will ship with clang (http://blogs.msdn.com/b/vcblog/archive/2014/11/12/visual-stu...). Yes, that's for Android (and, in the future, iOS) only, but it would not surprise me if that it is a sign of things to come: either Microsoft starts following developments faster, or people will move to clang for development. And I doubt the current Microsoft would be bothered if their customers moved to use clang, as long as they kept using Microsoft technologies (even if that's limited to running on Azure)
"First, let’s look at the C++11 language features. Clang 3.3 and above, and GCC 4.8 and later have complete support, so there was no point including them in the table."
Also note that, on the C++14 front, clang supported all language features and most library features. And that is a year ago.