Here are the blog aggregators on programming that I read. Feel free to suggest other interesting ones.

• Planet Smalltalk
• Planet D
• Planet Object Pascal
• Planet Lisp
• Planet Scheme
• Planet Clojure
• Erlang Central
• Planet Haskell
• OCaml Planet
• Planet Scala
• Ruby Corner
• Planet Python
• Groovy Blogs

There used to be a Planet Prolog, but it has gone defunct. I don't think Planet Tcl existed.