HTML5 + CSS + JavaScript, you mean? The future of the RIA looks great with the promise of these technologies; however, they are hardly a replacement for Silverlight right now. If you need to create a complex web application, Silverlight can do it, and although some browsers, such as Chrome, Safari, and Firefox, have already implemented parts of HTML5, the support is too jagged for you to create a stable cross-browser application.
Silverlight, however, should behave the same in all browsers in all operating systems.
Adam crossland
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