Well, people don't hack accounts, they send scam and there are some retards that fall in this tricks, they get scamed, not hacked. Also some people download what they should't and they download keyloggers accidentally, thats another reason for this "hacked accounts".
I recieved some scams by skype or in game, but i didn't believed nothing that they said after sending this kind of stuff.
Be carefull of what you download, be sure is clean of scam/virus/keyloggers, and don't put ur wow account mail+password anywhere except pandawow website.
Like this retard here: http://forum.pandawow.ru/showthread.php?t=193833,