A quick note: usually when you get an alert in the Toolbar, you worry.
This morning, an icon in the toolbar with an exclamation point boldly staring at me was a warning. Imagine my surprise when Windows Defender popped up and noted that there were no problems detected with my PC.
I like this feature: unlike the television network news, all news these days isn't bad news.
See http://www.microsoft.com/athome/security/spyware/software/default.mspx for more details.