Ive found a simple way to make it work on Windows XP x64

Simply download the x32 version from http://www.apple.com/itunes/download using your 32 bit browser and then get the 64 bit installer from http://content.info.apple.com/iTunes7/Win/061-4269.20080221.Wdwtn/iTunes64Setup.exe.

run the 32 bit installer and then open the 64 bit installer with WinRAR (http://rarlab.com/download.htm) or a similar program and extract Bonjour.msi and AppleMobileDevices.msi (or something like that).

open Add or Remove Programs (usually in Control Panel or can b accessed from Set Program Access Defaults link on the start menu) and uninstall Bonjour

Run the 2 programs u just took out of the 64 bit installer (bonjour and applemobiledevices)

Now u should have iTunes working with iPhone support however to get CD burning you must download GEARS 64 bit drivers from http://www.gearsoftware.com/support/drivers.cfm.

This may have been a marketing ploy on Apple’s part to underscore how Leopard supports running 32 bit and 64 bit applications and has a flat 32 bit device driver model (you only need write one driver for leopard.)

But iTunes isn’t the only piece of 32 bit only software out there that won’t run on 64 bit Windows…