Well, Krebs sees this as an extension of the attacks that took down his site a few weeks ago after he wrote about this research. So he wrote about it, attackers take down his site. His co-author Doug Madory speaks about it, attackers take down Madory's employer's site.

Krebs indicates in an update at the end that a source had heard rumors in criminal channels that an attack against Dyn was being planned.

Doug Madory's presentation was on the agenda for NANOG and so attackers would have had plenty of time to know about it.