It's interesting. Reading through the list, it was a lot of "things I learned a long time ago" interspersed with "things I learned fairly recently".
Having started doing web development before Django and jQuery were released, I definitely learned about JavaScript debuggers, POST requests, CAPTCHAs, AJAX (which, by the way, was positively painful before the invention of JSON), XHTML and the validation thereof, fake CAPTCHAs, cookies, passing session IDs in GET requests for people who block cookies, returning dynamically-generated images to an HTTP request... long before I ever learned about web frameworks, ORM, or any of those things.
Having started doing web development before Django and jQuery were released, I definitely learned about JavaScript debuggers, POST requests, CAPTCHAs, AJAX (which, by the way, was positively painful before the invention of JSON), XHTML and the validation thereof, fake CAPTCHAs, cookies, passing session IDs in GET requests for people who block cookies, returning dynamically-generated images to an HTTP request... long before I ever learned about web frameworks, ORM, or any of those things.