FYI, they got into TradeHill but couldn't compromise[0] any of the user accounts because of the architecture of the site.
[0] https://bitcointalk.org/index.php?PHPSESSID=r2dliaaebhrctppc...
[0] https://bitcointalk.org/index.php?PHPSESSID=r2dliaaebhrctppc...
I know that Bitcoinica, Gavin Andresen's faucet and TradeHill all got hacked through Linode's support system a while back, in which the attacker managed to reset all their passwords.