Ever since iTunes introduced Home Sharing, the Preferences dialog has had a checkbox titled "Home Sharing computers and devices update play counts". But this option has never had any effect whatsoever that I can discern.
You can rate the songs on your iPhone and the rating will appear to stick on the iPhone, but when you disconnect from the Home Sharing, the ratings you've just made are discarded. And the Play Counts in your iTunes library will never update.
Can this be fixed or is this just a huge bug since the beginning of Home Sharing?