Earlier quoted context omitted.
You missed the part that TFS is much more than just source control and since TFS 2012 also supports Git.
You mean like. Application Lifecycle Management? ALM? Bug-tracking, release-management and stuff? Which they now will be using Github for? Oh. That's definitely interesting.
Just like TFS, and I have seen many Java teams moving in, ditching various expensive products from IBM, HP etc. Team sizes or focus in HN might be different so TFS might be seen as dying, but it's not the case in the field.