You'll see not all of them have downtime (and the big ISPs, as always, show lots of complaints about downtimes), but a ton of those sites show a giant spike in downtime for a few hours.
So, once again, we'd like to point out that this is as problem that the internet community needs to start solving now. There's been a theoretical threat for a while, but it's no longer so theoretical. Yes, some people point out that this is a difficult thing to deal with. If you're pointing people to websites, even if we were to move to a more distributed system, there are almost always some kinds of chokepoints, and those with malicious intent will always, eventually, target those chokepoints. But there has to be a better way -- because if there isn't, this kind of thing is going to become a lot worse.