I agree with Trelja that people should stand behind what they say about a product. But I'm not sure forcing registration would solve the problem of people smearing a product for whatever reason. Anyone can create an email address and register under whatever user name they like.
I like Khokugo's idea of listing the poster's IP Address. That's probably the best defense available. You can access IP Addresses yourself at Audio Review by pulling up "Source" under the "View" window of your browser. For some reason, it doesn't work at Audiogon. As Blkadr said, Audio Review can be bad when it comes to smearing. I've checked the IP Addresses there before and confirmed in more than one instance that a single person was posting numerous negative "reviews."
I like Khokugo's idea of listing the poster's IP Address. That's probably the best defense available. You can access IP Addresses yourself at Audio Review by pulling up "Source" under the "View" window of your browser. For some reason, it doesn't work at Audiogon. As Blkadr said, Audio Review can be bad when it comes to smearing. I've checked the IP Addresses there before and confirmed in more than one instance that a single person was posting numerous negative "reviews."