Walmart just tried to undercut Amazon on, of all things, books. They’ve announced that they’re now selling the “top 10 pre-selling books” for $9 each, with free home delivery. Amazon has responded by dropping its price to $9 on the same titles, but their free shipping doesn’t kick in until you buy $25 worth of merchandise (or pay the annual fee for Amazon Prime). Price war!

Walmart is also now selling over 200 current best-sellers at at least half off the list price.

We randomly picked a best seller from the list—A Touch of Dead by Charlaine Harris—and compared prices, and Walmart was cheaper at $11.50 versus Amazon’s $13.47. With shipping, Walmart’s total price comes out to $13.47, exactly the same as Amazon’s price before any shipping costs are figured in.

As we wrote above, if you have Amazon Prime or bundle the book with other merch to hit the $25 free shipping mark, Walmart loses the price war. Still, it’s a pretty competitive offering, and we assume it will appeal to people who are already shopping on Walmart’s site.

Publishers and authors have been upset at Amazon’s $10 price point for new ebooks ever since the Kindle store launched, because they worry that it’s training consumers to expect an unrealistically low price that will never be profitable in the real marketplace—that is, in a world where Amazon and Walmart aren’t using books as loss leaders. Smaller booksellers can’t begin to compete on pricing, of course, so if you value your local non-chain bookstore you might want to keep giving them your business. For the rest of us, as long as the big retailers keep eating the costs of such steep discounts, it’s a great time to buy books. Or at least, new releases and top selling titles.

“Wal-Mart offers new books for $10” [Associated Press via Publishers Weekly]