That's right. The segmentation is about making sure that each site has a critical mass of experts, and enough of a focus that said experts won't be annoyed by off-topic questions. (Of course it's debatable where the line should be.)
Joel and Jeff have said several times that "Google is the UI". So the segmentation doesn't hurt the "answer consumers", who'll come in through Google with little regard for which site is which, while benefiting the "producers", who do care.
Joel and Jeff have said several times that "Google is the UI". So the segmentation doesn't hurt the "answer consumers", who'll come in through Google with little regard for which site is which, while benefiting the "producers", who do care.