I wouldn't personally. People have reviewed companies on the site I mod at and I've had those same companies threatening legal action soon after...
I think that this is the great fear. But, I want to know, then, how some of the other forums seemingly get away with it so easily? For example, every golf forum I occasionally read has a very extensive equipment section. On more than one, the equipment section is the most popular part of the forum (versus a swing advice section and a general golf talk section). Usually, people are sharing positive reviews about their new driver or whatever, but sometimes there are just plain ugly reviews. Sometimes people just have a really rotten experience with a club, with a company, with a shop, etc. But, I never see these taken down...
And, it's not just the golf forums. Lots of forums have reviews of products sections. Car forums usually have plenty of reviews. Pat care forums usually have reviews of products. Shoot, there are forums out there that are nothing but reviews -- like the Consumer Prodcuts forum and the Angry Consumer forum.
So, I just don't get what the problem is. You moderate it intelligently. If someone has a real problem, you let them post it. If they are just badmouthing the company you delete the post. Make the people have a good reason for a negative review, not just get online to badmouth something. You state at the top that the reviews section is only for person reviews. No professional reviews, no reviews by anyone "in the biz" etc. You make people have to give reasons for their opinions, not just "It sucks!" or "It's awesome!" And, you also state that the reviews are only the opinion of the poster, not the forum nor its moderators nor its moderators' mothers etc. etc. in all the necessary legalize.
Like has been said, there are reviews in the discussion section and many other sections -- I just don't see what the harm is in having a dedicated reviews section.
But, this has been brought up before, and ultimately it is William's board, so he can run it as he pleases.