It seems like it should be reasonable to have a review warning people reading them that many of the 5 star reviews are suspect as the reviewer was compensated by the seller.

No, because amazon is a marketplace, for example, a product can have more than one seller. because that the review is about the product and not about the seller. The right thing to do is complain about the seller on feedback and amazon delete all reviews from this specific seller buyers.

Wouldn't this kind of thing generally be coming straight from the manufacturer, or at least a fairly dominant seller for the product? Since they're paying for 5-star reviews of the product.

Could be, heh. I'm using amazon brazil, and here amazon isn't tooooo strong like USA. here in Brazil amazon works with other sellers in order to expand, but in a near future I really believe amazon will works like in USA.

Each state's Attorney General's office usually has a department of consumer protection that will hear these complaints. I've reported Amazon to my AG more than once.

What sorts of outcomes have you seen from your reports?

I was contacted about one of my reports, and gave them more information about what happened. I haven't gotten a follow up to that call, but I didn't expect to.

You can also report them to /dev/null, it will have the same effect.

> You can also report them to /dev/null, it will have the same effect.

Seems to be the same effect as reporting them to [email protected], then.

> Product reviews are only for reviewing the product, not the shipping, or the seller's practices. There are other ways to report this to Amazon, and you can report it to the FTC

The card soliciting the reviews was included as part of the product, so maybe just include the photo and focus the text of your review on the card (e.g. "It'd definitely a webcam, but this card that came with it totally ruined my experience. Definitely do not recommend."