The article does a fine job of explaining what we all know now about CAPTCHAs: "people farms" crack them. However, the article closes out pointing to a solutio

The article does a fine job of explaining what we all know now about CAPTCHAs: "people farms" crack them. However, the article closes out pointing to a solution that is a very hard set of problems to solve: behavioral patterns, Bayesian filtering, keywords.