Interestingly enough, I just learned that WordPress 4.0.1 also breaks certain shortcodes in a completely different way: http://the-digital-reader.com/2014/11/22/interesting-wordpress-bug-help-needed/ -- but those also appear to use custom shortcode parsing. Worse, even if the plugin author fixes the issue, the site owner will have to go back and edit all their posts using this plugin. A fine mess...