There's also such a thing called a "penalty volcano". If the person does not make swearing a habit -- most likely if it's the first offense they will only get a warning or a temporary (<24 hour) ban.

If they keep up with the bad language, their ban could get worse and worse -- 24 hours, 48 hours, 72 hours...

If they refuse to behave after plenty of warning, the ban will become permanent.


Continue reporting their behavior to GMs. It does take time for the GMs to fully investigate the matter (i.e. did you also swear? If so, they will likely take action on you as well). They will get what's coming to them -- Blizzard can be quite patient but they will do the right thing in the end.