App store ratings are both a blessing and a curse. They can offer prospective buyers a semi-objective opinion on the use of an app and be the means of pushing a wary shopper to a purchase, but that all kind of hinges on the user actually providing useful information or even not having a personal vendetta against you.
I can completely sympathize with users not wanting to get hoodwinked out of their own cash, but many app store reviews are actually pretty worthless, even ones rated high. But if that weren't enough, I got a really strange email last night, right on the heels of the release of my latest app, TF2 Recipes (weird formatting and terrible grammar/spelling left intact):
Creepy. Our friend 'Andrew' here is a complete scam. See, Andrew here doesn't want to foot the bill for downloading and rating your app. He wants you to give him a promo code. The problem, though, is that apps acquired on Apple's App Store with a developer promo code won't see their rating appear in the store. So essentially, our friend here wants us to wire him some money to perform a service he can't really pull off in the way he describes. Since the codes are only good for the app to which they're issued, I doubt there's an underground for promo code trading. Though he says that payment is only necessary after the reviews show up, it's hard to take him seriously with such an ill-informed business plan.
Ethics aside, this guy is a bozo. Even worse, though, is the implication that there might actually be developers that take him up on his offer, and assuming he actually does the work he claims, this adds taint to the ratings process. I'm not sure ratings are necessarily the best indicator of a successful app, but it's things like this that devalue them further.