Business pages on the wiki will eventually accumulate reviews as people use the [[Comments]] macro. People will leave both positive and negative comments and the quality of those comments will range greatly as well. If you are a business owner, try reading the quick start guide.
Critical Thinking 101 (need better heading title?)
The reviews you read here are worth what you paid to see them. Is the review all negative or all positive? Does it point out both good and bad points? Does it use proper English? Do they use slang or profanity? Do they complain about service, but you can feel their attitude in their review?
A high quality review will almost read like a story. They will tell you the story of their patronage pointing out both good and bad and giving you a context for their valuation.
Learning more about the Reviewer
So how do you know who the person who left the review is? Can you trust them? If they used their real name then it is a little easier, but even without that you can learn some things. Look at their username, does it have a dotted underline or a solid? Dotted usernames indicate that the person hasn't created a personal page on the wiki yet. Click on the name and then click Info and User's Info. How many edits have they made? Check a few, are they just a negative person in general?
Why do people leave reviews? More have motivation to leave negative reviews than positive for any business. Some may want you to give your business to either the business that the page is or, or another one.
Remember the aphorisms about customer service and the ratio between how many people a satisfied customer well tell, versus one who feels mistreated.
Why Negative Reviews aren't Deleted
Reviews are not deleted just because they are negative reviews. They may contain some useful information (even if it is information about the person who left the review). That is not to say reviews are never deleted; personal attacks on private individuals or "hit and run" reviews (made by an account created just to post a negative review) are generally removed. The remaining ones are the opinions of the community of Davis and are generally protected as such.
Another form of questionable review is somebody who makes an account just to slam a single subject. They might be named "AcmePharmacySucks". These reviews are often deleted and the person encouraged to post under their real name (or a pen name that we can get to know them by). It's seldom that you run into an actual Mr. or Ms. Sucks.
If something has gather a large number of reviews over the years, older reviews are generally archived to let the more recent reviews that best reflect the current community view of the subject to be more promanent.
How to spot Fake Reviewers
Reviews should reflect the opinion of real people. Some wiseguys create a number of accounts and try to appear to "be a crowd". These bogus account are generally referred to as sockpuppets, and experienced editors can usually spot them fairly quickly. Picture if you will Shari Lewis holding Lamb Chop. Look for edits being made from different accounts from the same IP address, but be aware that roommates can discover the wiki and legitimate posts be made from the same IP.
Recent court settlements point to this kind of activity not only being illegal, but also being actively prosecuted.