CodePlex Foundation (codeplex.org) by Microsoft is live.

We believe that commercial software companies and the developers that work for
them under-participate in open source projects. Some of the reasons are
cultural, some have to do with differing software development methodologies, and
some have to do with differing views about copyrights and patents. In general,
we are going to work to close these gaps. Specifically we aim to work with
particular projects that can serve as best practice exemplars of how commercial
software companies and open source communities can effectively collaborate.

The CodePlex.org foundation extends CodePlex.com, a OSS project hosting site.

Codeplex.org is aiming at bringing open source and commercial software developers together in a place where they can collaborate.

A great step in the right direction!