We are moving the Roslyn code to GitHub
This is getting terrifyingly close to my prediction that Microsoft should/would/will buy GitHub.  When I first started predicting this two or so years ago, it was mainly for its comedic value (it always got laughs, followed by "yeah, they should!" followed by nervous laughter followed by "wait, do you think they would actually do that?!"), but after the open sourcing of .NET I honestly think anything is possible.  Especially because the counter to MSFT buying GitHub was always "but... CodePlex!", and here they are explicitly moving a high-profile project from CodePlex to GitHub.  Scary!