Great points, but what system does have a notion of expertise? Wikipedia maybe? Google has many issues with SEO hackers and they've had a hard time filtering

Great points, but what system does have a notion of expertise? Wikipedia maybe? Google has many issues with SEO hackers and they've had a hard time filtering out the gamers. Hacker news requires up and down votes. I agree there is noise in any system and solving that is also a challenge to consider. Thanks for the comment.