Microsoft isn't going away soon as an enterprise server and platform vendor.  So there's little risk in building your server platform on Microsoft in the middle market.   It's important to build client interfaces that span browsers and mobile platforms, but the server layer is reliable and safe.   Nadella is a good choice to move Microsoft more aggressively into the cloud with Azure -- and they've got plenty of money to do it.   Congrats to the WhatsApp team and Sequoia on the sale to Facebook.  There are some lessons to be learned here in the middle market.