Question:
Why is it that until yesterday no one's transactions were affected by Tx Malleability DDOS attacks, but once MtGox declares it to be their issue, all the sudden everyone else is hit by the same attack? Is it copycat hackers at work?
Some possibilities:
1) The attackers became aware of the flaw only after MtGox made it widely known in their detailed technical announcement yesterday.
2) The attackers turned their attention away from MtGox to everyone else, after MtGox stopped BTC withdrawal requests.
3) The Bitcoin Foundation are behind the attacks, so that all exchanges and wallet providers become aware of the issue and are forced to fix their systems to prevent this from becoming a bigger issue later on.
4) MtGox are behind the attacks to divert blame, buy time and cover up their insolvency.
5) The attacker is someone who wants to cause panic, cause a market crash and then buy up cheap bitcoins.
6) A government (US, Russia, China...) are behind the attacks to try to discredit Bitcoin.
7) Russian hackers are behind the attacks and want you to enjoy watching Sochi (instead of sitting behind a computer all day).