Not sure I'd say new variants are 'needed'. But the fact that Lisp languages are so easy to write encourages people to write them. Besides, Clojure has some f

Not sure I'd say new variants are 'needed'. But the fact that Lisp languages are so easy to write encourages people to write them. Besides, Clojure has some fairly modern and novel stuff going on when it comes to concurrency, in addition to being a wholly modern Lisp.