With Microsoft's project related to Monaco and their VP's statement in the TechCrunch article that this style of development is where the future is vectoring towards, this is the first major platform vendor that has indicated that they see these sorts of cloud environments as not only as supplemental to core development, but potentially displacements.
Of course, there are years of engineering ahead before cloud systems can offer true displacement, but some of the early adoption scenarios are getting well defined. We attempted to capture the market size and early adoption drivers of cloud browsers in this quora post.
http://www.quora.com/What-is-the-market-size-of-cloud-IDEs-a...