When you ask Microsoft, “Microsoft WTF is going on with Silverlight 5? Is it the last version of Silverlight? Will you support more versions?”, you get given a link to the Silverlight Product Support Lifecycle Page (this has happened more than once to me). This page lists when Microsoft will support Silverlight until, and you will see that for releases 1 through 4 it was between two & three years. For Silverlight 5 it is a DECADE. This implies that this release will be with us for some time, so it is a good bet that it will be the last one. Before I continue this post is about Silverlight on the desktop not Silverlight on the phone which is a different thing all together, I have very different views to Silverlight on the phone.
So what does that REALLY mean to us? Mainstream support will end in 2021. Does that mean browsers will work & Visual Studio will work? Maybe is the real answer. Mainstream support (as defined on the Microsoft website) means
It does not mean tools or browsers will support it! Both are listed on the Silverlight page so they have given us this info too. Tooling is promised for a minimum of 12 months after release which means that Visual Studio & Blend releases 12 months following the release of Silverlight 5 will support it. This means we can expect Visual Studio 11 and Blend 5 to support it. However there is NO promise for further tooling updates, which means that VS 11 & Blend 5 are likely the last releases to support Silverlight. Visual Studio has a trend of 5 years support so expect bugs in tooling to no longer be fixed after that. The other tool we must consider is Lightswitch, which is based on Silverlight. What is it’s life? It is listed as 2017! So do not expect you current Lightswitch projects to continue until then!
In reality those are tools, we can continue to use them long after end of life (as the SQL team forces ANYONE who wants to create reports for SQL 2000 or 2005 will know). The real concern must be out customers and their interface to Silverlight, the browser. The support lifecycle page links to a page with supported browsers and has an interesting note. They will support those browsers until end of mainstream Silverlight support (2021) or until the browsers own support ends WHICH EVER IS SHORTER! So that means if IE ends of life sooner, they get to stop supporting it sooner. So when will that really end? The latest browser on the list is IE 9, so looking that up gives us nothing – it is a component and thus it’s lifecycle is linked to it’s parent product Windows 7 which ends of life in 2015! I am running the Windows 8 beta and I know Silverlight 5 does run on it with Internet Explorer 10, so if we assume that they follow the same lifecycle and this is the last release to support it that means we can expect browser support only until 2017!
So the reality is that your operating system, your browser & your tools all stop supporting it in 2017 – that is the real end of life to me, and that is 5 years away! Sure you can get security hotfixes for another 4 years after that, but really what good are those when your tools, OS & browser can not be fixed. So for me the real end of life is 2017.
Finally let be clear, there is assumptions and estimations based on previous support life cycle numbers. Microsoft could be preparing something and just not communicating it and this could all be wrong, but as Microsoft is not communicating this is all we have to go on anyway. There is another Silverlight, that one powers Windows Phone apps – I view these are two completely separate products (similar features but not the same, but different tools and different requirements) with the same name so my view here does not imply ANYTHING to Windows Phone 7 – I do believe that Silverlight will be with us for much longer.