[vincentdm]

As a Clojure user I very much agree with Rich's careful way of designing software.

But in case of the Clojure language itself, I'd personally prefer a big-bang version 2.0 with significant backwards-incopatible changes to clear up some accumulated inconsistencies, over a fork into yet another language with a new name. Such a fork risks splitting the community in two, each below a critical level, and also makes the decision to upgrade more open-ended (i.e. a 2.0 release explicitly supersedes 1.x and thereby communicates that it is supposed to be better and recommended. A fork is much more open-ended and provides more arguments to part of the community to stay behind).

But there is obviously a point where the original is sufficiently unrecognizable that a new name is more fitting.