I've never had my debit card frauded -you have to use a pin number with it, here anyway. However, I have had my credit card cancelled a few times by my bank because when they suspect that someone has copied the numbers, they cancel the whole series of cards with those numbers on them, or every card from that bank that has passed at that store within a certain amount of time. So while noone has ever managed to purchase anything with my card, it has been cancelled as a preventative measure a few times.
My friend had someone in Spain buy a bunch of plane tickets on her card this week... she never used her card there, lol! Her bank called her and inquired about the tickets... i'm sure the airline company voided the tickets so the idiots who bought them will get a nice surprise when they try to board the plane!
The new credit cards around here have a microchip in them, where you have to enter a pin number to be able to aprove the purchase, but not all stores have the new debit/credit chip processor, so some places still swipe the card, and it can still be used online with the numbers on the front and back.