These features do not seem as robust as Microsoft's (which I mentioned in an earlier post), which will allow the user to block Web sites based on a do-not-track list that users will be able to import to their browsers or create themselves. (See Microsoft's announcement for details.)
The comments posted by readers to the article about Google and Mozilla are generally disdainful of their approach - relying on industry to voluntarily implement the software that will make the privacy features work. Probably safe and legitimate sites will do so, but predatory sites will certainly not.
The comments also offer a few suggestions for dealing with this problem, including already available plug-ins (extensions).
Ken Pimple, PAIT Project Director