For some time developers writing applications for managed virtual environments have been enjoying the benefits of being able to interrogate and control the and generate code at runtime. When used appropriately these additional elements have delivered significant advantages - particularly in the tools world. Mocking libraries would not be easy to implement in a non-managed environment.
In the world of build management we have seen an explosion of tools that make it easier to deliver components and applications into a production environment.
One element of the picture that we have not seen a lot of progress on is environment control and deployment. Currently there seems little support for automated environment setup or deployment testing.