Used to be that you could tell how often you had played tracks etc, as there was a rating on each song, which was handy as you knew what you hadn't played much/lately/whatever...
Does this still exist?
I have turned on 'Rating' in the playlist, but this shows nothing...?
Thanks.

Of course this still exists, but it is not called "rating" (which is done by the user) but "play count" (which is incremented automatically if you have played at least 50% of a track).
It is possible though that you didn't configure the layout correctly, try playing with the width of the field, changing it to a custom width instead of the automatic one.

FWIW: it would be really helpful if you could state your Amarok and KDE version when asking questions, there are many versions out there and it helps to narrow down the problems.