"Bank industry officials point out that the attacks must be carried out by someone with direct access to an ATM switch, limiting the potential for abuse. But Litan said the limitation is hardly reassuring."
While the discovery is a bit concerning, the above indicates the implementation would be difficult, and ATMs are not alone in being vulnerable to this type of attack. If you are a trusted man-in-the-middle you can sniff bank details off the internet, the phone system, even the snail mail postal system. Hell, for the last 2 you don't even need to break any encryption.