You may have noticed that in Silverlight 3 RTW, there’s no more asp:Silverlight or asp silverlight-based media player controls. Those were removed from the core SDK and are no longer part of the official Silverlight distribution
What does this mean for me?
If you have an existing Silverlight 2 application that you are maintaining, you can continue to use the asp:Silverlight control. If you port it to Silverlight 3, you can also continue to use that control, but it won’t expose the parameters you’ll need for handling hardware acceleration or other Silverlight 3 (and later) specific features.
For new Silverlight projects, you should use either the object tag approach, or the extremely flexible but slightly more involved JavaScript approach. The JavaScript approach, in particular, will allow you to create a truly customized install experience for your customers.
But, but… I still love that control!
If you have a bumper sticker on your car that says “I ♥ asp:Silverlight” and you really want to use that control because it provides something you like (like, oh, simplified asp.net server-side access to initparams) you are not alone. There are enough people interested in the future of that control to warrant putting it up on MSDN code gallery.
A quick sidebar from my Silverlight book:
What Happened to the ASP.NET Silverlight Control?
The ASP.NET Silverlight control is still available as part of the Silverlight 2 SDK, and on the MSDN Code Gallery ( http://go.microsoft.com/fwlink/?LinkId=156721 ) but is not longer being maintained as part of the Silverlight 3 tools. The Object Tag and Silverlight.js approaches provide more flexibility. When porting your Silverlight 2 projects to Silverlight 3, you may continue to use the asp.net Silverlight control, as long as you update the minimum version number and add the required iframe if using navigation, but it is recommended that you port to one of the other two approaches.
So, there’s hope if you still want to use that control. :)