|P is for Practical
Unfortunately, this makes the ratings system kind of worthless....
I agree with you: negative feedback is easier to give. But I don't think it's worthless. I find it the most valuable.
When I shop at Amazon for example, I only read the negative reviews. The positive reviews are usually not useful; there is no accounting for taste and passion makes things sound better. Positive reviews tend to be full of emotional, fluffy language which has little specific content but can get you excited to buy something anyway.
The negative reviews are the most instructive because they tend to be either 1) ill-informed, ignorant, mean-spirited, or 2) cogent and specific with personal/subjective preference often discussed. From either of those I can usually tell more about what I'd think of a product than from the majority of positive reviews.
There aren't typically enough reviews on CPAN ratings to apply this strategy though. :( Works best with a handful of bad reviews to compare.