Also possible in C# with structs, interop annotations and
unsafe blocks.
And now you aren't using the language, but a (very) poor subset
of a language that doesn't even support templates.
C++ exposes SSE/AVX intrinsics, C# does not.
That is not correct.
1 - Nowhere in the ANSI/ISO C++ are SSE/AVX intrinsics defined,
those are compiler extensions. So equal foot with the C# EMCA
standard;
Duh, but every C++ compiler exposes this, so it is defacto
standard. C++ has plenty of non-standard standards, such as
#pragma once.
3 - .NET Native and RyuJIT have official support for SIMD
instructions, GPGPU support is also planned
I see on MS website an article about having a vector data type.
While interesting that isn't the same as exposing the actual
instructions, which will limit potential gains.
The aricle
http://blogs.msdn.com/b/dotnet/archive/2014/04/07/the-jit-finally-proposed-jit-and-simd-are-getting-married.aspx
Additionally .NET native will be MS only--
