Some persons are real jackasses, especially online. They will follow you, sometimes to different forums too, and all they do is insult and denigrate you... Just because they can. And sometimes moderators aren't just enough.
If this law can teach them how to behave in a civil manner, then I welcome it. Unfortunately some persons learn to behave and leave others alone only if they actually risk something, like a big fine or jail. Sad, I agree, but I even had to stop logging in in many forums to get rid of one of them... and this shouldn't happen.
Couldn't you say block them??? On Slashdot you can block people, on Google+ you can block people, and Facebook you can block people, and any email service you can block people, what major site can you not block people?