I am not a fan of baby talk at all! One thing I do often is mimic the sounds my son makes which I read can show you are engaged and paying attention to what they are saying. Aside from that the more diverse the vocabulary he or any child is exposed to the better. It's the same way with adults which is why reading is so crucial to the development of writing and expression of thought.
Thanks for the post!
RE: The language experiment on my child