If they had your address and A key they could probably crack your lock. A few years ago at DefCon they had a display showing people that if you hit a key in a lock hard enough it will open. YouTube still has video of an 11-year-old girl opening a lock after only a few hits. Kinda scary that they haven't fixed this for the most part already.
They key-from-photo concept is pretty spiffy though. If not a little worrisome to the more paranoid of us out there. ;)