In phpBB 3.0, bookmarking topics worked much like bookmarking in a web browser. You were not alerted when there was an update. As of phpBB 3.1, bookmarking is more like subscribing to a topic. You can be notified when a bookmarked topic is updated. Subscribing, however, will notify you when there is an update to a topic or forum on the board. Notification options for bookmarks and subscriptions can be configured in the User Control Panel, under “Board preferences”.