They aren't specific, and they are overwhelmingly large. There isn't a way to "fix" how general they are.
When a thread about Katanagatari is bumped, I can make a pretty good guess at what is being talked abut there. When an anime mega thread is bumped, there are thousands of potential anime shows, movies, directors, news, etc that could be being talked about.
Whatever I might want to talk about could easily get lost in that because when I post about Katanagatari there, Katanagatari fans there have no way of knowing that Katanagatari was brought up and people who don't care about the show have no way of knowing that something they don't care about bumped the thread. Instead, I could just make a Katanagatari thread so that me and the audience both know what kinds of discussions will transpire with no ambiguity.
