It should be noted that libel laws are still in effect. That means that companies can and will pressure authors to remove reviews through extortion - i.e. threat of a libel suit. Even if the threat is baseless, most people will remove reviews just to avoid a legal headache.

Believe me, I was threatened more than once, but I was way too busy to deal with a lawsuit. But, it still pisses me off.

As an aside, it's kind of f'd up that a company can even sue for libel. These were original common laws - i.e. person vs. person. Now, companies are 'people'. I am not a lawyer, so I don't understand the nuance. (which, btw, is also messed up: it's barely possible for non-specialists to understand the laws to which they're held accountable.) Rant Over.