The Zombie Stack Exchanges That Just Won't Die
It seems that we have a tag for book-recommendations, the first use of which was more about building such a service, than actually asking for a recommendation.
The second use is asking for specific recommendations.
In the definition phase of the site, the third highest ranked question was fairly similar, as it's looking for books that match a given requirement, but may be more objective as it isn't asking if they're necessarily any good. It doesn't meet that 'only one right answer' that the folks running Stack Exchange seem to have convinced themselves are the only good type of questions.
Where should we draw the line on this class of questions? If these questions aren't acceptable, are there ways to ask a question to get a useful answer that would be acceptable?
Update: I would assume that it'd be okay to ask if there exist recommended reading lists for a given topic for an age group or skill level. I'd say it's on topic, and I'm guessing others would do it you tagged it 'collection-development' instead of 'book-recommendations'. It's not really that different of a topic, and it again runs the risk of having more than one correct answer ... but I personally think it would be the sort of thing that we'd want on here.
Joe
The tag 'book recommendations' definitely implies that a specific book or group of books meets an individual need, e.g. a book about divorced dad who own a goat. They are questions that are probably unique enough for another site to be created, and would attract a lot of bibliophiles whose interest is in specific content.
How books can be selected to meet a certain audience falls into the 'collection development' arena. I think that the phrasing has to be right however, and it is the focus on the library users - rather than just a reference question for a single person - that will separate these two issues.
Given prior discussion here (http://meta.libraries.stackexchange.com/a/84/345) and the fate of Literature.SE, I'm going to have to go on record as supporting the consensus (however much I disagree with it) that providing professional Reader's Advisory is off-limits and general book recommendations even more so. Per the question and Deborah Mould's answer, however, collection development questions are valid but subject to a different tag.
We do need a "head" question type to draw people in for our "long tail," but this isn't it.