Gervase Markham blogged his thoughts on a “future” and “possible” function of browsers to act like anti-phishing tool e.g. Netcraft toolbar
With Netcraft toolbar (anti-phishing tool which is available to Firefox and IE browsers), user will report a suspected phished site. Once verified by Netcraft’s central server as phishing site, it will be added in the database. The next time the user or other users will visit the phished site, it is blocked. The reporter just saved the community from fraudsters. IMHO, reporting is always useful. Report suspected spyware, trojans, worms and virus to security vendors.
G. Markham wrote:
Then, older browsers which had not been upgraded, but which were blocking sites from a list including that feed, would still have some amount of protection from attack. As soon as it had been reported by one user using a new browser, all users using older versions would be vaccinated against attack from that site.“