My first opinion on this proposal was positive. I think it's a good idea. And the discussion supported that, ^ talking about allowing both positive and negative comments, mixed in with some promotion of the site and maybe feedback from the operator.
How does it add value to Flyertalk? By providing an avenue to discuss this segment of the travel advice market, an avenue to discuss what Flyertalkers have on their minds.... and bloggers are on our minds (for both positive and negative reasons). Adding FT to the place where this information can be found. (I will tell you for sure, I spend much more time on the bloggers sites these days and less time than ever on FT.) This adds to FT by keeping my/our eyes on FT.
The more I think about it, and the evolving comments, I am sure that FT will treat this like they have other commercial ventures, allowing only the positive dribble, and deleting any criticism. An edited blogger forum would just be a farce, you may as well sell paid space. An honest Blogger Forum would allow for both positive and negative, and be a benefit to the membership.