When I found that someone frequently posts really interesting topics I want to subscribe (to follow) to his/her new topic. There could be some way to get new topics of that author directly into wathed ones, for example, button “follow me” on user page.
Why can’t you click on (or bookmark) their profile and filter to topics? This view is default sorted by activity so all their new topics will be on top.
We should also have an RSS feed there if you want to subscribe to their topics…
This a right way to be if there are only few authors to follow and if there are only few new topics every day, if there are many it will be not convenient. If forum is huge and there are many new topics every day, and many interesting authors something like following can simplify discovering interesting content.