It looks like Microsoft is fully embracing the rich interactive features that Silverlight offers and have a new beta version of the Download Center that is Silverlight enabled. The beta gives a preview of some of the new designs Microsoft will be rolling out for the Download Center home page and category pages to make it easier to discover and download software.
The beta is currently for the entry pages only. If you decide to download any items you see, you will be alerted that doing so will exit you from the beta.
So far, the best new feature is the “live preview” of an item that gives you the description and a download link.