Based upon the insistance of a friend, I've written two plugins for personal use that I might open to the floor. I'm trying to gauge responsiveness to either of these:
Computed Fields - Like Calculated Fields, but it handles Math. You type in a simple formula such as "[Popularity]=[Number Plays]-[Skip Count]" and every time the song plays the plugin updates the library field with then new value. There's also a button which allows you to immediately Compute Fields for every item in a given Scheme, Smartlist, or Playlist.
History - I didn't think the [Number Plays] and [Skip Count] fields were good enough, so I created a plugin that creates a library field call [History]. Everytime a song plays, it stores the date, time, and the percentage played. You'll be able to go back and see that (Barry Manilow) - Mandy.mp3 played 76.87% of the way through at 2:43pm on 5/12/07.
I'm currently working on adding charting capabilities to the History Plugin so you can visually see how many times a song has played, when it was, and how much of the song played. This is a great way to determine if a song is liked, because if it's only played 51% of the way through each time, it'd be counted as Played versus Skipped in MC, but this plugin can track it. I'm also working on connecting the two plugins so you can use the values in the [History] field in a Computed Field (length of time between plays, average time of day played, average length of time the song played for, min/max a song's been played, etc).
Anyone interested in these plugins feel free to contact me directly, or post here.
-Tano