WPF/E is a subset of WPF (Windows Presentation Foundation) technologies from Microsoft. Microsoft is expected to make WPF/E available on wide platforms apart from Windows, including Mac OS, Mobiles and more.
When WPF/E was announced earlier this year in Mix ’06, I was little skeptical on how far Microsoft will go to make it ubiquitos and useful. With the Dec CTP release of WPF/E I guess I will have to eat my doubts 
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I downloaded and played with the Dec CTP (Community Release) version of WPF/E for last few days. The Dec CTP is small (1MB download), works in Windows and MacOS. The WPF/E browser plug-in works in both IE and FireFox – WPF/E works as a browser plug-in just like Adobe Flash. For me, WPF/E looks like a very promising technology for two reasons: 1) It is based (subset) on the same XAML specification – instead of making developers learn a new model, this is a good move. 2) It works as a browser plug-in, can make it ubiquitous. For WPF/E to complement Flash in a big way, MS has to come out fast with versions for as many platforms as possible, keep the XAML subset as close to as possible to the full-blown .NET Fx 3.0/WPF.
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