As a technology evangelist I must make an unofficial statement: “I have no idea”.
But I can look at history, which considering my advanced age, occurred during much of my life.
Along with SQL, Access, Visual Studio, Internet Explorer, and Windows XP, Microsoft has shown that it fully supports the tools, productivity suites and Operating Systems for specific periods of time. Naturally there are sometimes that the corporation makes changes to software that breaks software that others make, but so does all of the other products out there.
There has been no official notification that Silverlight is disappearing, that XNA may not be supported in the future that I know of, have you found actual, official data on this? Leave a comment.
Microsoft is a corporation and there will be changes, products get and lose support, Microsoft is a corporation and intends to make a profit, it is run by humans. Change is good and change is bad, but change will occur. But historically, Microsoft has shown that it will listen to the community.
It is odd that on one hand Microsoft is accused of not being innovative (it is extremely innovative, I have worked at companies that were the most “innovative” of their time and they did not even come close to Microsoft’s level of innovation. On the other hand, Microsoft is accused of making changes too rapidly or not supporting their current products or past products, but it does. This is the nature of an open marketplace, opinion, rumors, and factual information is all available equally to everyone, and it is up to you to figure out who to believe. This is a great benefit and a great burden. Guess right and you are successful, fail and you get feedback that you can use to make better decisions in the future.
But bottom line: I am thankful for the competitive technological environment in the world today.