No Silver Cloud?
On the day that Adobe appears set to announce no more Flash for mobiles, Microsoft is not far off from launching version five of its Silverlight web platform. And, it could be the last -- with serious questions being asked about its success and relevance in the modern Web world.
Silverlight was designed for rich Internet applications and powers serious products like Netflix and some of Microsoft's own sites. However, it hasn't picked up a massive userbase and in the mobile-focused world is looking increasingly out of sync. Also, Windows 8's Metro tablet interface won't support plugins, making Silverlight partially inaccessible.
Plugins are not the future for mobile browsing
The All-Device Future
Various rumors suggest V5.0 will be the last edition and it may even only support Internet Explorer on Windows. That will massively limit its appeal, with developers likely to move from Silverlight to other .NET and XAML tools when developing apps for Windows Phone, Windows 8 and so on.
While HTML5 and Silverlight aren't exactly synonymous, developers are cunning folk and should be able to figure out ways to make tools that fill in for HTML5's weaknesses. Because Silverlight can be written in .NET languages, there shouldn't be too much fuss in any transition, and with its relative lack of penetration, users really won't notice that much difference. But for mobile browsers, one less annoying plugin error message has to be a good thing.
Of course, Microsoft is under a lot less pressure than Adobe, having many other areas of income, and has decades of experience in marching to its own tune. It could well maintain Silverlight 5 for several years and evolve that product into another better suited to an all-device future.