Perhaps I'm dense, but reading the manual and numerous Google searches keep pointing me to "$wgEnotifWatchlist" as a solution, but new (and existing) users do not get the email notifications when this is set to true.
How can you set MediaWiki to send email notifications to changes on editors watchlist by default? This will go perfectly with the new default (as of 1.23) to add new pages and edits to a editors watchlist by default.
MediaWiki 1.23wmf8, PHP 5.3.3