i would argue that clojure is very successful i think (probably more like a statment of obvious) language success depends equally on the libraries available for it

clojure have a lot of libraries, and leiningen

and echo the "worse is better" slogan i think that languages that offer a little more feature above the current mainstream languages, will success more than languages that offer a lot more

most programmers are doers, they prefer to spend more time doing rather than learning

languages that are too smart ... are less likely to succeed not until the day ... they become only a little bit better than the mainstream

we move slowly from c to c++ to java to ruby ... the next big language is one that is only a little bit better than ruby ... not a lot better

i think clojure fit the bill