Live streaming isn't done by the main website, its separate or something so the people running that could easily get malware onto your pc (like pepsi said in the announcement thread a keylogger could have been put on your computer as well (so when you typed in runescape, followed by your details this information could have been picked up by a hacker if you did have that kind of malware on computer))... Make sure you do regular security checks. Could easily have been that website is what im trying to say, sorry to hear you got hacked btw