I think the ATF would sooner keep an illegal registry of firearms via 4473 forms rather than browse through gun forums looking for pictures of serial numbers to then try and determine who owns which account.From my perspective, covering up a serial number of a gun for sale/trade, etc. in a picture on a website is just common sense. I think most people realize that the ATF and the rest of gun-grabbing American Government have ghoul spies out there just looking for fodder for their gun-grab cannons. If you give them the serial numbers, you're just doing their homework for them and making their jobs easier...