With close to 50 e-book readers crowding the market, a price war may have been inevitable. But some industry observers say it was Apple's successful introduction of the iPad tablet computer—3 million sold in the first 80 days—that got Barnes & Noble to cut the price of its standard Nook e-reader from $259 to $199 on June 21. Hours later, Amazon's Kindle went from $259 to $189.

The iPad, which can do much more than provide reading material, sells for $499 and up. Those prices, too, may drop as other tablets emerge.

Meanwhile, if all you really want to do is read on the beach, consider that in bright sun e-readers' E Ink displays are easier to see than the backlit LCD screens featured on iPads.