I can't contribute to this very question, but there are other hurdles
to face in a Clojure port of Weblocks like the missing CLOS and MOP.
Leslie
Clojure is in the process of growing type/interface semantics that likely will
be usable in place of CLOS and MOP. They probably won't be a stable feature
for a number of months, but I'm sure that if such a port were to occur it
would definitely attract attention in the Clojure web dev community.
Andy