Today, Jackson said there might well be a connection between last year's attacks and those against Twitter, Facebook and others yesterday. He cited the circumstantial evidence of the dates -- Georgia attacked the break-away province of South Ossetia on August 7, and Russia responded the next day.

"There's certainly a lot constant hackers involved over there, but there's no chat about it at all in the usual places," Jackson said. "But I think it would be unusual for them to self-mobilize for an attack of this size, against one person."

That would add weight to the idea that a commercial DDoS operator might have been involved. If it was a Russian group that specializes in DDoS attacks, "the cost would be free," said Jackson, adding that it was conceivable that the botnet had been donated to the cause of hitting Cyxymu.

"Hacktivism is very much back," said McAfee's Marcus. "But it's really hard to say that this is the beginning of a trend, this targeting of individuals that leads to collateral damage [like the Twitter outage]."

On the plus side, Marcus said, when Twitter went dark for several hours the outage prevented not only the innocent, but also the criminals, who rely on Twitter as a launch platform for spam and malware distribution.