Eriisa: Eh, no, that doesn't make sense at all. Then all the boards would be cluttered with message "Hot topic on board XXX!".

If you want to know about threads on the Ludo board, you should read it (or view the RSS view). I'm not interested in many boards, but I am interested in this board. However, if this board would be cluttered with messages about hot topics on other boards, then I would no longer read this board. And then when there's a hot topic on this board, you would have to post it on the other boards so I can learn about them....