He does this not only in those notebooks but for example also in his "Paradigms Of Artificial Intelligence Programming" book. I have not seen this done to any serious extent in any algorithm textbook or tutorials.
I really like his Python code, but I think his Lisp code from PAIP is extremely underrated. In fact, it makes me sad he switched to Python for some AI tasks (same as Goodman & Tenenbaum in http://probmods.org) given that Lisp offers a unique feature for AI: homoiconicity.
This is something that I think will make a comeback with Bayesian program learning. For a glimpse of the future, see above link.
there are lots of lisp/fp books that aren't as known as PAIP. based on the few I took on ebay (henderson's recursion book and the likes) we might have a lot of surprises.
Where is this published? I couldn't look it up.