Probably not a lot. OTOH, we have a boatload of ATMs that do. As far as managing those devices, does Linux come with anything built in that will do this?
If you’re running windows ATM apps, have you upgraded your apps to work with windows 7 yet?
Yeah, when it comes to managing multiple independent systems (hundreds and thousands), you’re not going to beat windows for tools to do so. But then there are virtual Linux machines which overcome that issue in large part - not helpful in your case though, with physical devices that need regular maintenance performed. But then windows systems need more maintenance to begin with. :-)