I read the article and, for the most part, have an idea of what I had an idea of what it was saying. What my question then becomes is, why aren't all these new fake members showing up in vB or my third party member management system? Because regardless if a member fails to confirm their email because they provided a bogus one, their screen name still shows up and they get added to the total member amount.....which has not changed along with the hundreds of undeliverable emails I have been receiving.
I have the same issue. New user email notifications being sent to me and then when I go into admincp to search for them they don't exist. Mine is small scale compared to yours but of the dozen new user emails I received last night I can only find 4 in the DB.
[edit] What I have noticed though, in the main, is that the IP's these sign ups are coming from are COLOs. Now it could be that the ISP in question has a POP there but it seems odd that all of a sudden it's servers doing this rather than rooted PC's.