I recognize everyone's right to deal with criticism in their own way (as long as "their own way" doesn't involve things that are illegal, mmkay?). But, the flip side of this is if your way is doing something in public, or say on a social networking site, than I get to snark about it.
Now I understand that the author - reader relationship can be contentious. I can't tell you the number of authors I heard talk or write a collective, "Yes, exactly!" in response to Neil Gaiman's explanation of what exactly an author owes you book-wise.
And certainly I have seen rumblings in bloglandia when a book disappoints. However, if you essentially ask an author hey, how come that book sucked so much, I think expecting anything beyond, "I'm sorry that didn't work for you" is insanity. Even if you frame your question as, "Why is it, do you think, that so many of us think that your main character was stupid?" You haven't really changed the question. You've just disguised it as a literary question. You are of course, welcome to dislike a book or a main character. But I don't think the author has to apologize to you if you don't like something. Call me crazy.
But I can only imagine how difficult it would be to hear that a book critic dislike your book. I can even understand twitting* about your unhappiness. However twitting the book critic's email and phone number is a bit far. First, I am unaware of a critic's version of corrections. I have never heard of a scenario where a critic said, oh, hey, well, now that I know you guys like it, clearly I'm wrong. Certainly opinions can change over time. Certainly I've read books that I had an immediate reaction to that altered over time, sometimes even a few weeks.
However, that was due to my having more time to process, or possibly even discuss rationally with others. It was never because folks pestered me and told me I was stupid to have said what I said. (In fact, that's a sure way to keep me from revisiting my opinions.)
And the irony. The review wasn't even that bad in the first place.
*Yes, I know the prefered verb is tweeting. Twitting makes me chuckle, okay?