Until we can get ahold of the right people at AOL (which is proving difficult on a Sunday), you'll have to live without comment notification emails.
UPDATE: A friendly AOL ops engineer contacted us and unblocked us. It'll work again as of tomorrow morning sometime we're told. As for Yahoo, Gmail, etc... we'll be looking into those. For now check your spam/quarantine folders and add us to your whitelists if we show up there.