Hello to all,
I'm the maker of Njection Mobile (NMobile), an application available on the iTunes Application Store. It's a driving application that alerts you to speed traps as you drive by them, and we're adding support for alerts to traffic accidents and road work, so that you can be warned of traffic congestion before you hit it. Our goal is to keep drivers safe and driving under the speed limit.
As soon as we launched, our competitor posted a 1 star review on our app and then self reviewed his own app requesting features that we have added to his own.

We've still had decent sales, and no other 1 star reviews, but we can't help but to think that this has negatively impacted our sales. We're not a big iPhone development shop, and we
have a limited market, so a visible review such as this one that is basically an advertisement for a competing app is a problem. All signs point to this review as being from our competitor. The only other review has been on our competitor's app, and the same person has commented on every single article related to our app.
Look for Jim or Anonymous.
http://mashable.com/2007/12/17/speed-trap/
http://www.tuaw.com/2008/11/17/first-look-nmobile-a-radar-detector-for-iphone/
http://www.iphonebuzz.com/cheat-the-law-with-nmobile-175197.php
http://www.appletell.com/apple/comment/use-your-iphone-to-beat-the-police/
http://blog.wired.com/gadgets/2008/07/njection-brings.html
http://www.appsafari.com/maps/7063/njection-mobile/
http://www.macblogz.com/2008/11/13/njection-mobile-iphone-app-fights-off-speeding-tickets/
http://www.autoblog.com/2008/07/21/njection-updates-speedtrap-site/
http://www.iclarified.com/entry/comments.php?enid=2246#commentsanchor
And the sockpuppeting is not limited to reviews. This was a post in the iPhone Business Forum on Google that has since been removed:

Almost all of the registering account were either using a trapster.com email account or refer back to Trapster.com website. I use this example:
If a McDonald's employee walked into a Burger King, bought a burger, and faked salmonella poisoning, how would the customers walking in the door feel about eating there.
This is the same thing. I have contacted Apple several times and have gotten the same responce:
Please know that iTunes takes customer reviews very seriously. We believe in the iTunes community and their opinions on our products and we will not restrict the community.
A review will not be removed unless an extremely false claim has been made or a comment has been made that will offend a number of people.
We understand that you are concerned about this, however, all applications are receiving customer reviews that could potentially be unfavorable and most of these reviews will not be removed. If you would like, you can mark this review as "unhelpful" to move it to the bottom of the review list.
Best Regards,
iTunes Connect Support
All I am asking is that Apple enforces its own rules when it comes to placing reviews:

It's not that we can't handle a bit of competition, but we feel that this sort of thing really takes away us trying to communicate with the consumer the added value in our app. We worked with Microsoft on porting their Virtual Maps platform to the iPhone (which we were very excited about), and we spent a long time refining the app to create an experience that truly belongs on the iPhone. We really do feel that our application has added value, and these sorts of comments make it harder to get consumers to try our app.
The current system doesn't leave us much recourse to this sort of behavior. At least the ability to respond would empower us to address this comment and perhaps better inform consumers to things such as our better privacy policy and better software.
Thanks for your time,
Shannon Atkinson
Founder Njection.com LLC