I got this book because my friend Paul LaFarge had a piece in it. Plus, playing with history appeals to me. Unfortunately, few of the stories in the book really play with history. They're mostly a series of (a)historical fictions masquerading as metahistory, or critical history.
Paul's stands out as the one real alternate take on the history. He muses on the "discovery" of America. It was possibly the Icelanders, or the Danes, or the Chinese. Or maybe the Libyans.
The other stories in the book vary pretty drastically in tone and quality. Standouts are Alexander Chee's explanation for how many Native Americans were actually descendants of Chinese explorers is one particularly good one, as is Kate Bornstein's tale of Huck Finn as a transvestite prostitute.
Overall, though, neither the critique of history it sets out to be, nor as entertaining as a well-done satire could have been.