Jason Garms comments on the newly renaming of Windows Antispyware to Windows Defender... 

http://blogs.technet.com/antimalware/archive/2005/11/04/413700.aspx

Microsoft is proud to announce that the final name for Microsoft's Windows AntiSpyware technology will be Windows® Defender. We believe the name more accurately describes the protection that we offer to our customers against spyware and other potentially unwanted software and describes it in a more positive way. We expect Windows® Defender to be included in an upcoming release of Windows Vista. The engineering team has also been making progress towards the new signature distribution infrastructure. Windows® Defender will receive signature updates through the Windows Update infrastructure and will start appearing on Windows Server Update Services (WSUS) consoles shortly. The two new additions will be "Definition Updates" in the classifications and "Windows Defender" in the product categories.

Reminiscent of http://www.shockwave.com/sw/content/defender ;-)