Yup, on the fly track rating has been suggested before.

http://empeg.comms.net/php/showflat.php?Cat=&Board=wishlist&Number=24132

Don't know if it's under consideration for an upcoming release though. Usually if an idea is suggested and it's going to be implemented, one of the guys chiimes in and says it sounds like a cool idea. I didn't see that kind of response when ratings were talked about before.

I Am Not An Empeg Programmer, but it seems it'd just require a few bits on the player's scratch partition per song to store the rating, and, obviously, assigning a remote button to "rate" the song, and then to take the numbers 0-9 from the remote and then store that number. Then it could be integrated with the custom shuffle algorithms, so that when you put RATING in a custom shuffle spec, it uses that rating as a multiplier or whatever.

Hmm...