Interesting. But one of the points of Clojure is to get away from the object-oriented way so I'm not sure that I'd like Smalltalk.
Smalltalk, it is an experience, given that language, IDE and runtime/OS are all blended together, while Java can only do so much, even with the more advanced IDEs.
Clojure might be a reaction to C++/Java/C# OOP style, but it surely adopts Common Lisp OOP style.
I think it's worth learning, even if you never use it.