This morning I woke up to this statement in my inbox from Michael Coe, an AT&T Spokesperson:
"Beginning Friday, an AT&T customer was impacted by a denial-of-service attack stemming from IP addresses connected to img.4chan.org. To prevent this attack from disrupting service for the impacted AT&T customer, and to prevent the attack from spreading to impact our other customers, AT&T temporarily blocked access to the IP addresses in question for our customers. This action was in no way related to the content at img.4chan.org; our focus was on protecting our customers from malicious traffic.
Overnight Sunday, after we determined the denial-of-service threat no longer existed, AT&T removed the block on the IP addresses in question. We will continue to monitor for denial-of-service activity and any malicious traffic to protect our customers."
Now, I'm aware that this could just as easily be spin as anything, but given the proclivities of certain members of 4chan, it seems pretty feasible to me...although were they spoofing the 4chan-related IP address, or did they manage to piggyback onto 4chan servers? I dunno...