I am listening to this webcast, talking about dynamic dispatch on the JVM, and 19:30 it starts to get really interesting. The JVM is getting support for MethodMissing. As far as I understand, this is most relevant for compiler writers, but it is something that I really would like to have on the CLR (and exposed for C# & VB).
The reason for wanting this is very simple, it lets me handle advance scenarios very easily. Take a look at Boo's duck typing capabilities to see some of the stuff that can be done with it.