When does Amazon censor reviews?

Recently I wrote a negative Amazon review of the Motorola RAZR V3M. It's pretty but dumb.

Amazon didn't release it.

Odd. I've written hundreds of Amazon reviews, I don't recall one being rejected before. I edited my blog review a bit, and tried again.

Nothing.

Peculiar.

I went back and reviewed the other reviews of this phone. There were very few, and they were very weak. Some were negative, but they didn't say anything that might really hurt sales. My review would hurt sales.

It appears that Amazon is now censoring negative reviews of some products. Why this product? One hint might be that Amazon has a shady deal going with cell phones. If you buy on Amazon you get a significant cash discount -- but you sign up for a high margin plan. You have to keep the plan for at least six months, after which the cost of the plan equals the rebate you've received. If you don't cancel then, you pay through forever.

I've been trying out Amazon's "premium" plan (pay up front, get free 2 day shipping). I was toying with continuing it and paying for it. Amazon, after all, has been providing great value through their online reviews. Now Amazon has greatly decreased the value of those reviews for me. I trust them much less. I won't sign up for their premium plan after all.