With all this talk of type inferencing on the horizon and with the coming of Dynamic Languages to the .NET platform, one feature that I would love to see in VS.NET is something I call it Intellisense, with "Type Prediction".
The concept is actually quite simple. Since dynamic languages themselves have the ability to dynamically modify their types at runtime, it would be nice if the compiler were smart enough to "predict" (at compile time) which methods and properties that a class might have at run time. So, for example, if I had a class called MyDynamicClass, and if at some point in the the class' lifetime, I wanted to add a method called DoSomething(), then the IDE should be able to effectively guess which parts of the code have a DoSomething() method available and give me an intellisense listing of all its signatures.
Then again, since we're only at the cusp of even beginning to use dynamic languages on the CLR, it'll be quite a while before anyone picks up on this idea. Oh well. :)