Actually Star's interface is what you're describing. iTunesRating was even a tad simpler, the five dots/stars appeared on the menubar and all you had to do was rate directly on the dot/star desired to rate your song. I agree with WCITYMIKE in that it was most convenient, I truly loved iTunesRating.
@ Funes Developer: Congratulations on your app, seems like it suits your needs well, I also love to rate my songs directly from the menubar. I do wish the app was more direct (ala. iTunesRating) but alas, that's no indication that other users might find your app suits their needs perfectly. :) Keep it up!
(Version 0.4)