The security updates for Vista are also for Windows Server 2008. Windows Server 2008 will continue to get those updates until 2020 (edit: this is incorrect as Neemobeer points out below).
You can make a simple registry change in Windows XP so that windows updates thinks it is Windows POS Ready...
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Tyco Electronics Elo TouchSystems, the leading provider of professional touchscreen products, recently announced that its B-Series and D-Series All-in-One (AiO) touchcomputer families are now available with Microsoft's Windows 7 Professional and Windows POSReady 2009 operating systems.
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