Well, haliop is not that wrong.... I explain...
My experience on iOS store, for example, say me that much of the ratings are false.
If you surf internet you can find easily some site where you can buy 5 star rating for your apps.
I know is not correct to hype a forum friend app, but sometimes good apps doesn't raise the ranking, as the other publishers have more money than you to invest in advertise, and have 2/3 people that take care of a site to show their works.
IOS 7 will change the store again as they understood the ios 6 killed indie developers.
Some times i was forced to delete apps and upload them again with another name to try to raise the ranking, and it worked.
I think the star rating must be different, as the most of times, are wrong.... I think a 14+ years old can solve some of those problems.
Anyway, in the end, for me is not bad idea.
Long life to Steve!