Is it possible to enable/disable comment notifications for each author? Some authors want to receive comment notifications. Others prefer not to get notified.
This is or should be the default behavior. Generally, there is a checkbox, to request to receive notifications regarding comments for a particular post, see Comments Notification Link about also adding this function for members who haven't commented.
Updated: You'd want to use the same 'Comment Notification Link' provided above. Turn notifications of comments 'OFF' in Channel Preferences, and allow each author to subscribe to the article they want notifications for.
Additionally, if authors are posting from a SafeCracker form rather then inside the Control Panel, you can probably have them subscribe at the time of posting. If they are posting from within the control panel, you would either need an
custom extension to handle the subscription OR if you had a custom member field, that indicated an author wanted to receive notifications from ALL their posts, this could potentially be used to somewhat automate that process.
But if you want to give authors full control, then let them subscribe to comments.