Yeah, I agree: Two of the languages with the best autocomplete and introspection in general are Common Lisp and Smalltalk. Some of that's simple maturity, but it proves that those features can work very, very well in even the most dynamic languages around.
Sorry, but I'd contest that remark, at least for Smalltalk. It only has the best autocomplete/introspection for people who have never worked with modern statically typed languages/IDEs and/or significantly large projects. It just doesn't have the neccessary information.
