Are banking apps really running under Windows? whats the point? shouldn't they be using Linux for added security? Damn those guys are crazy. Do ATM machines have anti viruses installed or what?
I wish I knew about the traditional banking system as much as I do about Bitcoin (and I don't know much, but it sure helps being able to read the code because its open source..)
I don't know if banking apps run under Windows, but I know those high stakes gambling machines do. I once watched a repair technician fixing one, and I could see the windows system while he was doing it. Those things can take thousands of dollars of a single gambler in an hour, though they produce a winnings slip for big wins that you have to exchange for cash. ATMs probably use windows too.
ATMs in Britain definitely use Windows. Until 2004 they ran on OS/2, then migrated to Windows XP. If that sounds terrifying, you should check out "Windows for Warships" - an exciting mix of Windows 2000 and XP!