I just started listening to this audio book yesterday . . .
Karr is an engaging writer (and reader) who makes this interesting point: when asked about the rise in popularity of the memoir over the past ten years, she says that people who crave realism in their narratives have turned to the form in response to the current interest in dystopian, speculative, and/or experimental, academic fiction.
I have no way of knowing if this is true or not, of course. But it makes sense to me. People's stories--the "I" narrator--have always fascinated me.