The evidence comes in a report released today by software testing firm SmartWare. The company tested each browser against the same phishing sites flagged by contributors to Phishtank, an anti-phishing network run by OpenDNS. Firefox blocked 243 phishing sites that IE7 overlooked, while IE7 blocked 117 sites that Firefox did not.
I guess you can feel good about using Firefox over IE for this reason, but really, a bragging right would be in order if the numbers were even lower. 117 is still a reasonable number, but that left about 20% of sites not caught in the filter. Of course, using common sense could personally reduce that number to 0.