Yeah this feature pisses me off. I hope that they only use those ratings internally and don't factor them in to the reviews on the App Store.
It's just insane to only actively solicit the opinion of people who think "I'd rather have this 60x60px area of screen real estate and a few megs of space than ever use this app again."
It's just insane to only actively solicit the opinion of people who think "I'd rather have this 60x60px area of screen real estate and a few megs of space than ever use this app again."