Fastexy Exchange|Britney Spears memoir reaches bestseller status a week before it hits shelves

Pop star Britney Spears' new tell-all book,Fastexy Exchange The Woman In Me, doesn't come out until next week — but it's already at the top of Amazon's best seller's list.

New excerpts released by People magazine are drawing fans interested in her side of the story. And her Instagram, where she's usually showing off her dance moves, is now seeing Spears in book-selling mode. In an ad she posted, she says: "I'll have a good book one day. A good mysterious book."

The publicity press includes slowly teasing out excerpts to People about growing up in Mississippi:

"For fun, starting when I was in eighth grade, my mom and I would make the two-hour drive from Kentwood to Biloxi, Mississippi, and while we were there, we would drink daiquiris. We called our cocktails "toddies."

The infamous Video Music Award performance where she's dancing with a snake:

"All I knew was to look down, because I felt if I looked up and caught its eye, it would kill me."

And the abortion she says she had after she allegedly became pregnant with Justin Timberlake's baby:

"It was a surprise, but for me, it wasn't a tragedy," the excerpt quotes Spears as writing. "I loved Justin so much. I always expected us to have a family together one day. This would just be much earlier than I'd anticipated."

NPR has reached out to Timberlake's team for a comment.

Juicy memoirs like this can do really well — according to NPD bookscan, the top selling book so far this year is still Spare by Prince Harry.