The performance claim doesn't really matter in a world where we use languages like Python, Ruby, PHP and Javascript for major applications. Also, compared to these languages, Common Lisp seems to generally be faster (and, on most implementation/architecture combinations, supports real parallelism).
http://benchmarksgame.alioth.debian.org/u64q/compare.php?lan... http://benchmarksgame.alioth.debian.org/u64q/compare.php?lan... http://benchmarksgame.alioth.debian.org/u64q/compare.php?lan... http://benchmarksgame.alioth.debian.org/u64q/compare.php?lan...