Yeah, I just saw that:
http://www.cnn.com/2011/TECH/gaming.gadgets/05/04/sony.anonymous/index.html
Come on, I highly doubt Anonymous is THAT stupid.
During the investigations, which have gone on for two weeks so far with many online networks offline, Sony discovered a file on its system named Anonymous that contained the group's sort of catchphrase, "We are Legion," wrote Kazuo Hirai, the Sony Computer Entertainment president and America division chairman.
http://www.cnn.com/2011/TECH/gaming.gadgets/05/04/sony.anonymous/index.html
Come on, I highly doubt Anonymous is THAT stupid.