What should I do in this situation in C#

Silverlight

Provide support for OnPropertyChanged() for auto properties

Shift Types for Bitarray

C# Support for C Styled functions and Binary compiled C#

C++/CLI or C# winform test in different OS

Extend 'using' keyword functionality (C#)

[C#] Simplify foreach statements when using linq to allow using where and order by in the language.

C# Implement an "in" or "oneof" operator

Add C# extension properties