The only real news here is that, indeed, ASP.NET vNext is going to be developed in the open, or at least to some extent. But right now, not a lot of code seems to be released that wasn't already out there (although I did not go through all the repos).
I don't think you should expect to find many current/legacy parts of ASP.NET that aren't open yet: this seems to be mostly for new stuff.
Finally, don't forget that "ASP.NET" doesn't seem to mean a lot (anymore): it's basically Microsoft actively shipping the org chart. Anything that's web related and from MS appears to get tacked "ASP.NET" on front of it. Cause really, what does ASP.NET MVC, basically a pretty uninspired Rails port to C# (and just an open source library like any other), have to do with "active server pages"?
[0] https://aspnet.codeplex.com/wikipage?title=MVC [1] https://entityframework.codeplex.com/