Why Silverlight May Yet Displace HTML

There’s a live discussion over at sogrady’s blog whether RIA’s will ever gain a foothold on the web. Stephen points out that HTML had been adequate for most online tasks people wish to do today - webmail, search, banking, and that AJAX is useful in filling in the gaps.

On the other hand, David (who works at Adobe) rightly points out that people [will] gravitiate inexorably to better experiences.

I would like to point out some technical reasons why I believe of all the RIAs that are going to be deployed, Silverlight stands in a good position to start carving off browser realestate  from HTML.

1. Microsoft has learned to embrace the existing ecosystem. Silverlight, being text based, can be served by Apache and PHP. 
2. In addition, Silverlight can be embedded in existing HTML markup. This makes it extremely attractive for web designers and developers to incrementally deploy Silverlight applications. Look out for a Silverlight version of SIFR soon.
3. There is no separate compiler. Taking cues from the web browser, the absense of a separate compilation step means users are free to tinker, view source, and learn from other users. There’s going to be a lot of plagiarisation, copying and adaptation of published Silverlight markup, and the ecosystem will flourish.
4. Silverlight content, being text-based, is indexable. For instance, this may mean that video streams can include subtitles based on Silverlight markup. Anything that helps search engines find your content is always welcome.
5. Silverlight offers a sane model of embedding and integrating Silverlight content (read “Widgets”) from other websites. Current approaches, such as using embedded javascript and iframes are really hacks, and lack a sane unified component model. Being vector based, these widgets will be able to fit into different page layouts. (Question: Is Silverlight still restricted by the outdated cross site remote access rules?)
6. The runtime is small enough that Microsoft is in a position to “push” out it’s plugin widely and by default. (Although I believe there’s a dependency on the .Net runtime, which is HUGE).