Actually, it is a hacker, and it really could be anyone, from a friend to a stranger my friend is having the same problem right now and i am currently tracking the kid down.
Also, you would be surprised how many kids hack Facebook/Myspace/AIM/ect. everyday, people just dont have lives anymore.
That might be a virus/bug Rhyb, as opposed to a hacker. Not sure what to do about it though, I haven't had those sort of problems in ages! *touches wood nervously*
Your password wouldn't be "guessed" so much as a program would go through various combos for them (by them I mean the scum that did this) That's why it's always recommended to use symbols and numbers in your password. A trick I use is to replace "a" with @ and "i" with 1, used in an unlikely word, like stickytape = st1ckyt@pe
Two friends of mine have had their facebook profiles hacked, and they started posting Viagra-type spam advertisements.
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