How many reports have you had to fill up with a number of stars to choose? How much useless time is spent on figuring the this number just because it is always very ambiguous?
Some blogger wrote an interesting entry on Why I Hate Five Stars Reviews. Basically he advocates binary voting instead via like/dislike. Maybe a ternary system via like/dislike/don't care would be ok too.
One coworker used to advocate the same for a similar reason: people reading those reports only pay attention to the extremes: the 5 stars or the 0 stars. So if you want to have a voice, you need to express it via 5 or 0, nothing in between.