Some features that are missing right now:<p>1. A proper list structure instead of arrays.<p>2. Macros<p>3. A richer numeric tower.<p>4. FFI<p>What other major changes are needed in ecmascript before the bastard child of cl comes of age, to become the new lisp? Or is there something big I am missing which makes it impossible?<p>John Resig has a nice overview of Ecmascript 5 at http://ejohn.org/blog/ecmascript-5-strict-mode-json-and-more/<p>Plus tail call optimization is coming soon to SpiderMonkey, https://bugzilla.mozilla.org/show_bug.cgi?id=445363