re: Banks Struggle To Get ATMs Off Windows XP
I don't understand why banks are having such a tough time. Granted, XP's resource requirements are different than WIndows 7 so a new motherboard is probably a good idea but aside from installers and applications that do not follow guidelines dealing with registry access and where to write user-context files, Windows 7 should run Windows XP applications. However, if the ATMs make use of older peripheral standards such as serial ports, parallel ports or other custom expansion boards that interact with the ATM's mechanics, that could cause a lot of fustration. Although there are USB-based adapters for these older technologies, I've found many to have extremely poor quality drivers leading to unreliable peripheral operation. An unreliable ATM or one that fails to feed bills (but thinks it did) would lead to unhappy customers and high support costs.
IMO -- this is probably not as much of a software problem as it is a hardware problem.
Regarding being unsupported and failing PCI audits -- that's a huge issue but I don't think it will be a security Armageddon. If banks lock down network access and use white listing technology that monitors executables on disk and in memory (plus NX or XD chip tech that prevents code execution in data areas), the system is pretty difficult to compromise.