a hacker in my definition is a someone who brakes stuff to fix it and learn from it, or brakes it to make it better. Does not matter what does he brake - software or hardware, it is still the same. I guess I can say I am a hacker, not that I "hack" websites to fuck them up, but I like to brake stuff to make it better, or make something new out of other things...
Oh and yeah look at that debate, it is all explained.