It's an optional download with m/s updates m/s tells me it delivers high quality video and richer website experience whatever that is
Has anybody used it or using it ,is it worth downloading
If you want to view websites which use Silverlight then, unsurprisingly, you'll need Silverlight to view them. If not, having Silverlight is completely pointless.
Despite all of Microsoft's attempts to promote Silverlight, very few websites currently use it. So you can probably do without it. However you'll get frustrated if, for example, you try to view Ryanair's route map without it:
http://www.ryanair.co...p-flight-destinations