Well it seems that Microsoft has decided on naming it's Antispyware tool ... It will be part of the upcoming Vista release.

The tool, designed to protect PCs against hidden software, has been renamed "Windows Defender" and is getting a new look as well as capabilities to detect rootkits, keystroke loggers and other threats. The news of the revamp came Friday in a posting to a new Microsoft corporate blog dealing with malicious software.
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Sounds more like a cartoon hero name to me ... Windows Defender ... Defender of the weak ...mmmmh are they reffering to something

C.