For me it's all the simple stuff. I don't know how many times I've typed in string _name; in a VB.NET class and gotten an error.
What really gets me though is all the damn TYPING I have to do when I'm just trying to inherit from a class or implement an interface and define out it's methods. Thank god the IDE will fill in the interface methods for me. Even when it does, there's no consistancy. I hit tab in C# but in VB.NET I have to hit enter. Then I have to go delete the linebreak that hitting enter puts in. That's annoying.
All of the shadows, implements, inherits, notinheritable, blah, blah, blah, etc... crap really keeps me from enjoying programming in VB.NET. Too much typing.