@Miller,
I think it would be a mistake.
Other than providing the owner(s) of the site with revenue, I can't see an up-side.
It won't serve as a means to filter some of the more inane or ugly contributions. In order to post comments on articles at the Washington Post site, one needs to subscribe. It's not cheap. Subscriptions do not, at all, prevent inane or ugly comments from being made. Nor does WaPo's use of word filters. Commenters have shown ingenuity in finding ways to get words like "****" and "****" through the filters.
(As a side note, just the other day I saw a post at WaPo from our old friend kuvaz. He uses the same picture of one of one of his dogs as his icon)
I hate the idea of monitors. All of them will have some sort of bias or we'll get the silly absolutism found in "zero-tolerance" policies in schools.
Craven has provided us with two very effective tools to filter what we don't want to see.
We can argue all day as to what it means to use the "ignore" feature, but if one finds another member to be reliably obnoxious or absurd, it's a simple thing to remove them from one's sight.
The thumb feature has, I think, been distorted into a way of scoring "points" for or against other members, but if used, as it was intended, one can eliminate the sight, at least, of the same comments being posted and re-posted in slightly different ways.
There are often times when it appears that a thread has been dominated by a discussion in which I have no interest, however if it's a discussion (which is to say a give and take between at least two members) there's nothing to object to, and, again, I can rid my screen of it by using the thumb feature.
One person's passionate argument may be someone else's boring dreck, but how would it enhance this forum to have someone with the power to make the decision as to which it actually is? Some may be pleased, but others will be offended.
I also really have no idea why anyone would pay anything just to read these discussions and never post a comment. Is there really anyone out there who does this? I guess we'll never know.