Windows XP SP3 build 3205 is the first official & authorized release of the next Windows XP service pack; and has been made available to testers as a part of the Windows Server 2008/Windows Vista SP1 beta program. NeoSmart Technologies has the run-down on the included 1,073 patches/hotfixes including security updates. Contrary to popular belief, Windows XP SP3 does ship with new features/components, most of which have been backported from Windows Vista. Some included features: 'New Windows Product Activation model: no need to enter product
key during setup. Network Access Protection modules and policies have been brought to XP after being one of the more-well-received features in Windows Vista. New Microsoft Kernel Mode Cryptographic Module - the Windows XP SP3 kernel now includes an entire module that provides easy access to multiple cryptographic algorithms and is available for use in kernel-mode drivers and services. New "Black Hole Router" detection - Windows XP SP3 can detect and protect against rogue routers that are discarding data.

http://neosmart.net/blog/2007/windows-xp-sp3-beta-build-3205-released-analysis-included/