Silverlight supports the display of high-definition video files, and importantly, Microsoft will do the heavy lifting of sending them over the Net. Streaming large media files is expensive, but Microsoft will (optionally) host Silverlight media files and applications. This will enable smaller developers to deliver large and high-definition files quickly and reliably, without paying content distribution network fees. Microsoft is promising reliable 700kbps throughput for media files, and free distribution of all content on its network for one year. After that, distribution will continue to be free up to 1 million streamed minutes a month. Fees after that have not been set.

Also, Silverlight applications are delivered to a browser in a text-based markup language called XAML. That's no big deal for Web users once they land on a site. But search engines, like Google, can scan XAML. They can't dive into compiled Flash applications. Flash-heavy sites do often wrap their applications in Web code that search engines can crawl, although it's extra work for developers and designers to do it, and may not yield search results that are as good as they would be if the search engine was indexing the actual application instead of keywords tacked on after the fact. Silverlight applications will be more findable.

Hope that helps!!

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