While they made their target (just – they originally said “by the end of 2011”), Microsoft’s growing move towards modern web technologies such as HTML 5 and CSS 3 and away from Silverlight is becoming clear. For example, the release was publicised by a single blog post on MSDN, and made public at 9pm on a Friday – probably the second worst time you could possibly choose (after 3am on a Sunday) to make an announcement you actually want people to hear about.
It’s not as if Silverlight 5 doesn’t come with a bunch of features SL devs won’t like – it’s packed with new features that enrich the platform (even if it is dying). There’s a whole 3D stack included in an XNA 3D API, with built in effects and a full XNA content pipeline. H.264 (unprotected) is decoded in hardware, XNA boosts low-latency sound, P/Invoke, multiple windows, 64-bit support in Windows, Full Trust mode for enterprise with unrestricted filesystem access, and all kinds of other features.
However it seems Silverlight’s days are numbered, as Microsoft moves to HTML 5 for its Windows 8 tile apps and improves its support in IE 10. If you’re still interested, you can get it from Silverlight.net.