[migueldeicaza]

We are working on replacing those parts that we can.

But there are several issues:

* reference source code not being portable and not working on Unix. * complex dependencies between the portable and non portable pieces * some bits were only released recently, and without those it was not possible to port other chunks * dynamic happy code high prevents some code from being adopted as Mono can be used as a full static compiler on iOS, Xbox and Playstation.

So as time permits we will bring those over.

We also plan on supporting the "core" model where our contributions will flow back upstream.

But "core" is still a bit undefined