Introduced way back in iPhone OS 2.2, the “Rate on Delete” feature was a great example of how even Apple sometimes get it wrong.
The intention, of course, was to prompt users to actually rate the apps on their iPhone in a non-intrusive way, but if you never deleted an app, you were never prompted to rate it. Combined with the fact that people deleting apps tend not to care much for them and you had a system that promoted app reviews but with a slant to the negative.
Now MacRumors is reporting that Apple has fixed its mistake and removed Rate on Delete from OS 4.0
I’m not sure this is the right tack. You still want user ratings, it’s just the current system skews towards bad ratings. Why not supplement Rate on Delete with a one-time Rate prompt the fifth time you open an app? That would cover all the bases.