Credit Card Fraud -- A new use case for me

I found a UPS envelope on my doorstep today and in there was a new credi card from American Express.

American Express monitors all account for fraud on an ongoing basis. Our fraud detection systems determined that you name and card number may have been intercepted by an external party and, as a precautionary measure to protect your account against unauthorized use, we have issued the enclosed replacement Card.

This happened before -- kinda. They called and asked if I was trying to book a flight from London. While I wish I was it wasn't me in London. They gave me a new card then.Today this came and I hadn't talked to them recently.I checked the recent transactions and nothing came up looking odd.I'm not even on using the online Playstation gaming network.I wonder what triggered this. I've not been hanging out in any seedy parts of the internet. (Or at least not any new seedy parts.) The FAQ specifically says "American Express cannot disclose information regarding ongoing fraud investigations."Odd.It's just a pain in the butt to now give everyone my new card that regularly bills me for stuff. Oh well. I suppose it's better than the alternatives.