In the blog post that's an breakdown of ms project, yes. Used to show how ms is doing with open source? yes. because .net framework (and implementation of runtime,compiler/blc) was owned by ms (mono is another implementation of the runtime/compiler/bcl).

But for some components is ok to contribute there:

- mono(xamarin) was already migrating to use open source components like the bcl (corefx) after the initial open source of code by ms. It's like dont write two times the same stuff.

- coreclr: the .net core runtime

- corefx: the standard library (base class library like io etc), used by .net fw (win) and .net core and partially by mono

- roslyn: that's the c#/vb compiler, also mono is trying to reuse that

- cli: it's the sdk for building projects. Can the project system changed? yes, but not needed now (.net core it's boostrapping another xplat runtime so need tools). as a personal note, the cli team doesn an awesome job to make it easy to contribute

and some notes:

- asp.net is a web framework, it's used a lot, nice ppl contribute. who like servicestack/nancy/suave, use that instead.

- fsharp (http://fsharp.org/) was and is already driven by community, and lang decision are in repo https://github.com/fsharp/fslang-design by community and lead by @dsyme

And you should also check dotnet foundation pulse and community projects (like Nancy/Nunit/Akka.net/mbrace).

Lots of the work done by ms can be useful for others, see Kestrel server (damn fast) who can be used by other web projects like Suave (https://github.com/SuaveIO/suave is a lib, not a framework :D)

- dnx was the predecessor of cli, and replaced by it (good job by aspnet team to boostrap xplat on netcore)