This probably also means Unity3d will soon be able to use an updated version of Mono, because Microsoft wants to back them and doesn't force them to pay the full licence price.
Seriously unity could already do it without the old mono runtime with what MS offer : the Roslyn compiler for C# and the LLILC a MSIL bitcode to LLVM compiler for iOS, and the netCore runtime for android. Their C# to c++ compiler seem now a misguided way.
I'd like the option of that! Unity and C# are a great pair, but I'd love to have the newer C# features rolling out.