Allow a user to be notified of the activity on a page that they liked

As member of a knowledge sharing community that has liked a page, I could benefit from receiving notifications on the following events:

• when the liked page changes
• when the liked page gets deleted
• when the liked page receives comments
• when the liked page is liked by other people

This can be achieved by expanding the autowatch feature to include the liking of pages (adding a page to the watch list automatically upon like).
A question, though, would be about what should happen when the user unlikes the page (remove from the watchlist?)