From Walmart.com

When Wal-Mart, Amazon.com and Target started getting into an online price war over top-selling books, it seemed only a matter of time before the battle moved to other products. After all, Wal-Mart and Target are trying to pump up their ecommerce efforts across the board, not just with books. Now, we're seeing signs of a new round of heavy discounting on DVDs.

As with the books, Wal-Mart started this one, and is following the same pattern: offering the top ten pre-selling DVDs online for about $10. Amazon and Target matched Wal-Mart's prices on select titles, and Wal-Mart shaved a few more pennies off.

Wal-Mart seems to have something to prove after a recent New York Times story asked if Amazon, which has been steadily expanding its product selection, is becoming "Wal-Mart of the Web." Wal-Mart has chosen books and DVDs — two of Amazon's signature products — to launch the online price war.

Of course, there's a lot of discounting that goes on online as part of the holiday shopping season, but Wal-Mart, Amazon, Target are selling these particular books and DVDs at prices that are guaranteed to lose them money. It will be interesting to see where the cat-and-mouse game moves next. Blu-ray discs or CDs?

One side note: even as Amazon and Target engage in the price war, Amazon is continuing to run Target's ecommerce operations. Target recently said it is dumping Amazon as a partner, but the divorce won't kick in until the two companies' contract expires in 2011.

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