We must be getting close now – Microsoft today have released information on the Microsoft download site about Windows XP SP3 – http://www.microsoft.com/downloads/details.aspx?FamilyID=68c48dad-bc34-40be-8d85-6bb4f56f5110&DisplayLang=en
The update will be up to 580MB and is only for the x86 / 32bit versions of Windows XP.
From the Download site
Windows XP Service Pack 3 (SP3) includes all previously released updates for the operating system. This update also includes a small number of new functionalities, which do not significantly change customers experience with the operating system. This white paper summarizes what is new in Windows XP SP3.