Short answers to common questions.
Yes, you can update articles after a release, see Overriding Articles Revision.
For all other updates, you'll need to cut a new release to Clojars.
See also: Testing & Verifying
Cljdoc has in many ways been inspired by clojuredocs.org but besides documenting Clojure itself, cljdoc tries to provide documentation for the library ecosystem around Clojure.
The projects are not related besides both pushing documentation in the Clojure ecosystem forward 🤗