We’re thinking more about this now that our API is nearing.
In the meantime, note that you can block any member from following you or posting comments on your content (look for the Flag icon on the member’s page).
Please don't do this.
Might do. This often turns out to be joke/comedy accounts and suchlike, but maybe we can find out a way to make it legit.
Couldn't you look at the activity of the user and check out the account a little bit?