Here are the features that i would love to see in Silverlight:
- Allow users to copy text from the UI (Or was the UX argument an excuse for playing with new toys?)
- MSTEST (I know that Silverlight Unit Test Framework exists.)
- Triggers (including data triggers)
- Typed data templates
- Uniform XAML (WPF: <Style TargetType={x:Type local:Foo}/> vs Silverlight: <Style TargetType={local:Foo}/>)
- Uniform validation API (eg: Data Annotations has three flavors)
- XAML with less namespaces (doesn’t really matter if you’re a designer only type)
- Support for Desktop (‘regular’) .NET assemblies. As long as Desktop .NET assemblies are not supported, tools that automate the process of generating a ‘shadow’ .Silverlight project (eg: Prism has for each project a silverlight project that, ignoring the different assembly references, exists out of file references to the orginal project).
- UniformGrid
Note: This list is not exhaustive and may change in the future.