Big surprise at that.
Publishers Weekly posted a list of top selling books in 2009. I've linked where I have my reviews.
I did not read a single hardcover fiction book that sold 100,000 copies or more and the only non-fiction I read was Superfreakonomics.
I have read some books that were successful in trade paperback form in 2009:
My second least favorite book ever, The Time Travelers' Wife.
Malcolm Gladwell's Blink and The Tipping Point.
David Sedaris' When You Are Engulfed in Flames and Me Talk Pretty One Day (the best Sedaris book).
Elizabeth Gilbert's Eat Pray Love.
John Steinbeck's Of Mice and Men.
Junot Diaz's The Brief Wondrous Life of Oscar Wao.
Mark Haddon's The Curious Incident of the Dog in the Night Time.
Erik Larson's The Devil in the White City.
Steve Lopez's The Soloist.
Muriel Barbery's The Elegance of the Hedgehog
Albert Camus' The Stranger.
J.D. Salinger's Catcher in the Rye.
Per Petterson's Out Stealing Horses
More than I thought. And some good ones among them. Niffenegger was the only one I hated. Diaz was a zero-star review. All the rest were one-star or better.
16 out of 547 books. Less than three percent. Not the publishing markets target demographic to say the least.