The link is to "Internet Explorer 7 Popup Address Bar Spoofing Test." If you then click on the link in that page to do the test, and you're vulnerable, it opens a popup window that says something like "If this hadn't been a test, we could have..." AND your browser's main window takes you to a spoofed microsoft.com.

If it's a test to see if bad people can do bad things to your computer, then good people will have to try those same things. If your firewalls or whatever are protecting you, then the test will show that you aren't vulnerable, or perhaps you'll receive an alert telling you of a threat, lik Cruiser did.

Discovered by clicking on link. I have an anti-virus program and firewall that are updated daily, plus two anti-spyware programs that I updated two days ago. No alerts, but then the test indicates I'm vulnerable. I don't use MSIE7, though, and I'd ignore messages claiming to be from Microsoft, even if they were from Microsoft.

It's up to you, though.