This article http://www.theinquirer.net/inquirer/news/2334577/banks-negot... suggests that the problem lies (at least partly) with other bank computer systems which are running vanilla XP rather than the ATMs themselves which may be on XP Embedded, and that it is a substantial problem, with big UK banks apparently cutting special deals for extended support. EOLing WinXP seems to have turned out to be a nice little source of revenue for Microsoft...