If I want to tell iTunes I don't really like a track very much (but don't want to uncheck the track or delete it from my library) should I rate it as one star or leave it with no stars? Which would iTunes consider to be the lesser rating for a track?
One star is certainly rated higher than none, but in practice, marking one star for the songs you really don't want to shuffle is a great practice.
I have several "utility" playlists to weed out songs and having one star is one of the exclusionary criteria for the source of iTunes DJ
my zPartyTracks smart playlist criteria are all of:
As I've got many songs rated above 1 star, those never seem to show up in playlists that prefer higher rated songs, and the one star songs are relegated to being specifically included even though they did get one star.
No stars is a lesser rating than one star. This can be verified by sorting a playlist by rating, and having at least one song on it with one star, and at least one with no stars. The one with one star will float above the one(s) with none.