Amazon’s EC2 servers were used to launch the attack on Sony’s own servers, according to Bloomberg.
Neither Sony or Amazon have commented on the matter. Anonymous still “didn’t do it” – although they suspect that one of their factions working on ‘OpSony’ (the anti-Sony campaign of theirs) has splintered, apparently going rogue from the already rogue ‘organisation’ that they belong to, and hacked PSN.
Meanwhile, Sony are steadily restoring functionality, and they expect to see worldwide online gaming again by May 31. If you haven’t already, turn on your PS3; apply the mandatory system software update and change your password.