Comment 2 for bug 709172

Straw-man proposal: The average rating for a software item, as shown to someone running a particular Ubuntu release, should be the mean of the latest 50 ratings for versions of the software that are less than or equal to the latest version available for that Ubuntu release.

From there, probably the biggest improvement would be to weight ratings for newer versions more heavily than ratings for older versions. If we did that, maybe it would no longer be necessary to limit it to the latest N ratings. Or maybe that would still be desirable for performance reasons.