A bunch of people seem to be ashamed of enjoying the Dr. Dolittle books. I remember reading a bunch of them as a kid but I don't remember anything particularly shameful about them -- my memory is that they were sort of Jules Vernesy in their way. I do remember there being a whole lot of them available at my local library.

I remember really liking 'The Sword of Shannara' by Terry Brooks, then rereading it years later and being appalled by how derivative it was and its atrocious writing. I also read a bunch of other Terry Brooks books, but gradually lost interest. (Towards the end of this process I remember reading that he was a lawyer and realizing that this probably could have been deduced from the plots of the last few books of his that I read.)

I agree with something that one or two people said in the discussion you linked to, which is that it's not all that embarassing to admit that you liked something that wasn't very good when you recognized that it wasn't very good when you read it in the first place -- the real embarassment comes from having genuinely thought that something was good which you now realize (or at least think) has no redeeming qualities. I therefore don't really mind that I used to read a lot of David Eddings, for instance.