I read an article about a year ago that about 50% of China's ATM had this serial number recording capability, and that at least some compuer-connected cash counters had it too. I was highly sceptical, but then I found a cash counter that had this capability listed on its specifications page. I don't have time right now to find it again, but they are out there and it's already being done at some places. Okay, maybe not correlated, but recorded for sure.