It is an incredible amount of features, but Blender goes through a lot of updates with mostly bug fixes as well. I know a lot of the added features in this rel

It is an incredible amount of features, but Blender goes through a lot of updates with mostly bug fixes as well. I know a lot of the added features in this release (Spherical Stereo, Bendy Bones) underwent development for quite a while, and the fact that they've stabilized around the same time might be more coincidence than anything else. As far as codebase health and its sustainability, I think the role of the Blender Foundation, and a very enthusiastic community has made Blender what it is today. Plus there open movie/games has disproportionately shaped its development.