It's actually sponsored by the moderator.

I really don't see any harm.  I'm sure it's an attempt to generate activity on the board and I haven't seen it turn ugly.

Hi All. I'm a newbie, and enjoy all the banter on here, and learning the correct way to hobby. My question- Why are the good reviewed providers listed on shill friday log? What does shill really mean. Sorry about the stupid question....

But I have no idea where you found this 'shill Friday' log.  I'd be interested to know where it is because I have no knowledge of it on this site.  A shill post is one made by a guy who just wants to recommend a certain provider on a particular, usually,  regional board just because he thinks she is the bomb, or that she asked him to do it.  Those posts are usually deleted by the mods as they are seriously frowned upon.

Swim

an individual shill post is frowned upon. Disallowed I guess.
However on the Atlanta board the mod posts a "Provider Friday-Hobbyists, Who's your pick of the week" thread and it requires a providers name in the subject line and a link in the post. It's interesting to see each week who is included. I guess you could call it a shill post but it's the only one on the Atl board and it's once a week on Friday. ( as the title makes clear). This is likely what the OP is referring to.

This originated on the Florida board several years ago, and is popular there.  Many may consider this to be shilling, but in my case I post as a shout-out to the lady if I had seen her that week.  Whether any other hobbyists consider or do see her as a result, I could care less.  

As for why the good, well-reviewed ladies are mentioned most prominently, it's because they are good.  Also, those that are mentioned tend to be actively engaged on the boards, and will likely read, and maybe respond to the shout-out.

technically speaking, the Provider Friday threads really are shill posts.  I suppose they are allowed because they do not just promote a single provider, but as many as the guys want to nominate.  I have participated several times on my home board, Florida.  I just have never seen it referred to as a 'shill log'.

Swim

I thought of a Shill as someone who benefits without disclosing that he benefits. The most egregious form being a self post.

So, I would disagree with: "A shill post is one made by a guy who just wants to recommend a certain provider on a particular, usually,  regional board just because he thinks she is the bomb" If a guy really likes the lady, I don't see that as a shill. Maybe over zealous, but not a shill.

But, I would agree with: "or that she asked him to do it." That implies a tit for tat, and not a truly honest post.