Let me get this clear.....neither of you had an authenticator on your account? nuff said
While this comment has validity. I have been playing MMOS for many many years(starting with Beta for Everquest) and have never had to have an authenticator before. I am the only person who uses this computer. I only use it for WOW( I use my work computer for email, facebook etc), and I run a virus scan every other day.

That all being said I did make the mistake of checking wowheroes by a recommendation from a friend and as careful as I am I got a virus and a compromised account. I havent decided if I am going to get an authenticator or not even now. I will just have my laptop up and use that to check websites for WOW information.