Clojure for Lisp Programmers

http://blip.tv/clojure/clojure-for-lisp-programmers-part-1-1319721
http://blip.tv/clojure/clojure-for-lisp-programmers-part-2-1319826

It's a great talk. I've seen many people on /prog/ groundlessly criticizing Clojure, and it's sad. It this presentation Rich Hickey addresses all their points and provides a coherent rationale behind Clojure and its various ``unusual" design decisions. Despite being quite lengthy it doesn't get tedious as it quickly jumps from topic to topic, sometimes with interesting questions form the crowd between the jumps. You should definitely watch this video before forming your opinion about Clojure.

>>10
Other than breaking referential transparency, you can't be sure that your code will do what you mean: since it works outside your namespace, someone may rebind a procedure used inside your procedure, without even knowing it will break your code.
Do you know about packages? Do you know that because of this purity-crap Schemes's SYNTAX-CASE is as complex as rocket science and Scheme is a failed and dead language?

Common Lisp: defmacro
---------------
Scheme/Racket: defmacro begin-for-syntax syntax-e syntax->datum syntax->list syntax-property #' (void) quote-syntax datum->syntax syntax-parameter-value syntax-rule raise-syntax-error internal-definition-context? syntax-parameterize make-set!-transformer prop:set!-transformer free-identifier=? syntax-local-value/immediate syntax-local-transforming-module-provides? syntax-local-module-defined-identifiers syntax-local-module-required-identifiers make-require-transformer (require (lib "stxparam.ss" "mzlib")) syntax? (require mzlib/defmacro) define-macro syntax-local-lift-expression (require racket/stxparam-exptime) make-rename-transformer syntax-local-require-certifier make-parameter-rename-transformer syntax-local-value define-syntax-parameter make-provide-transformer syntax-local-provide-certifier syntax-source local-expand/capture-lifts local-transformer-expand/capture-lifts syntax-local-lift-values-expression syntax-local-lift-module-end-declaration syntax-local-lift-require syntax-local-lift-provide syntax-local-name syntax-local-context syntax-local-phase-level syntax-local-module-exports syntax-local-get-shadower syntax-local-certifier syntax-transforming? syntax-local-introduce make-syntax-introducer exn:fail:syntax make-syntax-delta-introducer syntax-local-make-delta-introducer syntax-case define-syntax syntax-rules with-syntax syntax-position syntax-line syntax-column ...