After being a .NET developer for a few years and also developing in Flash I'm impressed, this has huge potential. Thanks Charles and Scott for the video, that explained a lot.
I've got a question about control development. After playing with Expression Blend and using the new BookViewer control (very neat) there looks to be a huge potential market for Silverlight custom controls, just as there is for .NET user controls, Flash components,
On first glance, the disadvantage for component developers appears to be the difficulty in protecting IP. XAML and JS are all clear text - great for passing through the firewall, but easy to reverse engineer.
Sure, you've got your code-behind file that's compiled, but the majority of the functionality of many controls will be rendered in XAML, which can be read by all.
Maybe I'm missing something? Takeup of Silverlight will be enhanced by having 3rd parties providing ready made controls, what's Microsoft's plan to support this secondary market?