I feel your pain. People can leave bad reviews without even trying your application. they can leave reviews that are in a broken english that actually make ZERO sense (on the US appstore) and give you 1 star. You can click the report a concern but I have never seen Apple actually take a review down.
Any high school kid who's mom bought him an iPod Touch can leave a review like "this should be free"...1 star. And there is nothing you can do about it because Apple did not think far enough ahead about this whole AppStore process because they were in such a rush to get it out the door.
Basically, us developers are OUT of luck and just have to let our applications speak for themselves.
BTW, if Apple is listening I hope reviews that mention other apps will be disallowed. One developer's reviews should not be used by another developer to promote their app.
Xanthos, I totally agree. I had a developer or one of his friends come to my app and review it and say "oh this app is too expensive so I bought this other awesome app XYZ instead". When app XYZ doesn't do 1/10th the functionality of my application.
That will put a lot of "Drive-by reviewers" out of business--so sad. 😉 What it won't do is keep the competition from buying a copy and then writing negative reviews.
This is a huge step... but I'd still like the ability to email a reviewer. I got a similar sabotage 1 star review. Since it's in a country where it is the only review, all sales there have stopped. I'd at least like to find out what they didn't like. 1 star is a pretty strong feeling.