You have a lot of nerve posting a blog like this and/or are showing how out of touch the Exchange team is with its customers and reality.
"The Exchange engineering team is hard at work developing the NEXT version of Exchange" with focus on Office 365.
However, the engineering team should be hard at work finishing the CURRENT version of Exchange to make it stable and useable for on-premises customers.
One year after it's release on-premises users are still not able to do something basic as forwarding a meeting request to another user, we get complaints about this almost daily.
"Running Office 365 also brings us real-world experience that helps us build a better on-premises product. " and "Our development strategy continues to focus on Office 365 as the initial platform where we roll out new features. This approach allows us to introduce and test new features at scale before including relevant functionality into on-premises updates. The benefits of the strategy can be seen in Exchange 2013 ..."
On-premises customers have not been able to see these benefits or a better on-premises product at all. Despite it's issues with rollups, Exchange 2010 was a much better on-premises product, and while you are regularly deploying new Exchange 2013 builds on Office 365, we are still stuck with an unstable CU2 build with lots of unfixed issues and we have received untested broken updates.
You guys are still pretending that Exchange 2013 was a succesful release for on-premises customers and something to be proud of, when in fact it has been a complete and shameful failure so far, having caused lots of reputation damage. The whole NSA PRISM situation won't exactly help adoption of the Online version either for many customers.
Your blog is not giving us much confidence that this situation will improve going forward.