Microsoft mice and keyboards currently have basic functionality with the 64-bit versions of Windows. In order for advanced features like Magnifier and Tilt Wheel to function, IntelliPoint and IntelliType Pro version 5.5 device software is required. Version 5.5 supports Windows XP Professional x64 and is available via web download now.
Notice: The intellitype 5.5 software is still not avilable to download atm of this message. (Thanks DKI)