Microsoft's version of Github (kinda) and yes it did. A good place to get free TFS hosting if you need it. Also a lot of .NET open source projects are hosted there, so a good place for inspiration and learning.
Umbraco is an Open Source .NET based CMS. As always open source projects can teach us a lot about how things can be done properly (usually).
Here I opened one of the unit test files just to show how they do unit testing in that project. This project uses a lot of the same technologies we use. Should be helpful.
Play around with it, you might just learn something :).