I'll interpret that as a dig against the App Engine and not Clojure... even though it's clearly aimed at either Clojure alone or the combination with GAE.
Anyway, are you being serious (i.e., in your experience is clj+gae noticeably slower than java+gae or python+gae?) or just funny? Since I've never done any serious profiling of Clojure on GAE, I'll bite and do some brief performance tests and report back.