With having so many, and perhaps many members having a lot as well, would this not put a load on the server forever emailing?
I don't choose the email function. Im here to check it every day anyways, so I just go straight to my User CP and check them out. I imagine the ones with a few hundred or thousand do not have email being sent to them for every one of those as that would be annoying getting an email for each of those threads.