Microsoft have announced via Microsoft Technet that they have released Service Pack 3 and users can expect updates at the end of this month.
Chris Keroack, Release Manager of Windows XP Service Pack 3 said in the announcement:
Today we are happy to announce that Windows XP Service Pack 3 (SP3) has released to manufacturing (RTM). Windows XP SP3 bits are now working their way through our manufacturing channels to be available to OEM and Enterprise customers. We are also in the final stages of preparing for release to the web (i.e. you!) on April 29th, via Windows Update and the Microsoft Download Center. Online documentation for Windows XP SP3, such as Microsoft Knowledge Base articles and the Microsoft TechNet Windows XP TechCenter, will be updated then. For customers who use Windows XP at home, Windows XP SP3 Automatic Update distribution for users at home will begin in early summer.
Service Pack 3 will include some important updates including Microsoft’s updated Management Console 3.0, which appears in Windows Server 2008 and Vista, and an update to Wifi protected access. There will also be a “health checking” component added that’s already used by Windows Server 2008 which can check to make sure that certain upgrades and security features are in place for XP-based clients before they are allowed to log onto a network.