Funny you should mention this -- a psychologist friend of mine in Seattle and I were talking about this a couple of weeks ago, and she mentioned this -- and said something along the lines of, "well, I guess we know who the really well-connected fans are!"

I know that acknowledgements are lovely, and do like them in academic books. But that conversation made me wonder if to some extent acknowledgements in fiction, especially sf/f, can help to foster feelings of 'important' vs. 'ordinary', or 'in-group' and 'outsider'.