I think it's part of the joke
The Dullest Blog in the World is just that -- dull post after dull post designed to evoke (and successfully doing so) long strings of wonderful comments.
But there hasn't been anything new there since July 2, despite the site's promise of "a new season of uninteresting content shortly."
I picture the author of that blog sitting back and smiling as the hopeful hits keep a-comin' in. After all, what could be duller than a dull blog that isn't updated?