I think it's too early to tell where the quantitative ratings are or aren't useful. There's definitely a fair amount of "like/dislike" based voting, as well as attempts to manipulate/game the ratings in various ways, which is entirely expected. A big question is whether, when looking at the trends in the overall rating data or on specific articles, it's possible to translate these ratings into meaningful action (e.g. articles that may need tagging/cleanup, undetected vandalism, articles that are candidates for promotion, etc.), or whether there's too much noise in the data to do that.
To answer that question, we'll have to let the ratings play out for a while, and look at the data from different angles.
But, I do agree that soliciting more specific feedback and action (other than direct edits) is likely to ultimately have more impact. What do you think of the ideas in Article feedback/Extended review?
How long is a "while"? How long do you estimate it would take to get enough data that would actually be sufficient to translate it into meaningful action? For the lesser frequented articles that may actually need the meaningful action I anticipate it would take years!
There is no way in which we can increase the volume of ratings for articles that receive a small number of visits unless we change the positioning of the AFT to make it much more prominent , which is not planned. The ramp-up of AFT to the English Wikipedia was completed yesterday so we are now able to collect and analyze data across a much larger number of articles than the previous 3% sample. We expect to have new results ready to be published in the coming weeks. If you have specific questions, please post them in the AFT research talk page or on specific research subpages: 1 - 2 - 3 - 4.