Truth be told, CodePlex is fairly popular in the .NET world. TypeScript simply is a JavaScript project, plays well with Node, NPM and Jake - I think it makes sense for it to be on GitHub. It's not the first MSFT source base hosted on GitHub, probably won't be the last. Heck, I work at MSFT and keep all my open source code on GitHub.
I wouldn't read too much into that though - huge company, a bunch of projects and different audiences. CodePlex has an audience - there's a bunch of cool projects on there, too.
True - but remember, there's a bunch of teams building stuff. Most of Open Tech's and Azure's open code bases are on GitHub. TypeScript isn't the biggest MS project on GitHub and I just want to make sure that nobody is using this as a "CodePlex is dead!" data point.
I wouldn't read too much into that though - huge company, a bunch of projects and different audiences. CodePlex has an audience - there's a bunch of cool projects on there, too.