You don't have to be paranoid but just respect a couple of simple rules. One of them is creating a hotmail address that is only used for your character in game. Also do a regular scan of your computer not only with the antivirus that is installed but from time to time with another antivirus (some sites offer a free scan even if they don't remove the infected stuff), and use a difficult password. You will be surprised how many people use passwords like 12345 or abcde for a game account.
Many players login from a school computer or other public computer, it's not so difficult for a hacker to install some malware on a school computer and retrieve a login and password from a forum. If the info is the same as your account info it's bingo for them.
