E-tailer Amazon.com (AMZN) is making a big splash with the second coming of its popular Kindle e-book reader, but how does it stack up to the competition? The Kindle 2 won't begin shipping until the end of the month, but we had a chance to play around with it, along with other models from companies like Sony, Astak and Bookeen. Below, our impressions.

For anyone who hasn't been initiated into the cult of e-readers, handheld gadgets that digitally store hundreds of books and periodicals, they've been hailed by avid readers as a high-tech antidote for bulging bookbags and smudgy newsprint fingers. The market for these devices is still small between 700,000 and 750,000 units have been sold since 2006, according to Forrester Research. But it's growing fast, with some 80 percent of sales coming last year alone.

Indeed, some experts predict that e-readers could transform (read: digitize) the publishing industry the same way MP3 players did the music business. While at this point it's pretty much a duopoly together, the Amazon Kindle and Sony readers rack up more than 95 percent of sales more than half a dozen models are currently available, with more expected this year. Here's how five of them compare:

Bookeen's Cybook Gen 3 ($350)
Astak's EZ Reader ($300)
On the surface, the Bookeen's Cybook Gen 3 and Astak's EZ Reader appear strikingly similar. They each weigh less than half a pound and easily slip into our inside coat pocket. They also feature 6-inch screens, store up to 1,000 books in their internal memory and boast enough battery life in a single charge to turn 8,000 pages. Pretty impressive. Yet when we turn them on, the black-and-white screens make us feel like we've been transported back to the Ozzie-and-Harriet era. In fact, no model to date offers color, and because the screens themselves are gray, analysts say they don't always offer the sharpest contrast.

Indeed, many of the illustrations and book covers stored in the Cybook are grainy and hard to see. And it's too easy, we find, to accidentally choose the wrong title, since the button that moves the cursor is small and too close to the one that does the selecting. A company spokesperson says publishers provide the images and that navigating the library, while intuitive, can be tricky if many books are stored in the memory.

We find it much easier to choose from the titles listed in the EZ Reader. But when we try to boost the font of the Dickens classic "Oliver Twist," the text rotates sideways, and we have to keep pivoting the device whenever we want to access the menu, making it feel like, well, a not-so-easy reader. The company says its new model will include a touch-screen menu so that rotating won't be necessary.

iRex Digital Reader 1000S ($860)
The iRex stands out for size: Its screen (10 inches) and weight (more than a pound) are nearly double the size of the others. While it's too big for anyone's pocket, it does slip easily into a colleague's handbag and can store PDF versions of more than 800 newspapers (for $10 to $30 a month). It also includes a stylus that we use to write notes directly onto e-books like "The Three Musketeers."

But with its top-heavy design, it feels like it might somersault from someone's hands onto the floor. "It's a concern for us, too," says Jeff Paleczny, president of eReader Outfitters, which distributes the iRex. There's also that eye-popping price tag. For the price of the 1000S, we could get two of any other model.

Sony PRS-505 ($300)
Amazon Kindle ($360)
That leaves the two industry heavyweights: Sony's PRS-505 and Amazon's Kindle. From an aesthetic standpoint, Sony's sleek metallic design trumps the competition. It's simply more elegant than Kindle's white plastic casing. Its high-contrast screen and easy navigation make it highly readable and maneuverable. And if you want to pony up for the deluxe model, Sony's PRS-700 ($400) includes extras like a touch-screen menu and a highlighting tool, especially useful for students.

Not that Kindle's first incarnation was ever a slouch. On top of nifty features like a built-in dictionary and electronic highlighting tool, it was and still is the only reader that lets users wirelessly download content.

But despite all the fanfare, the long awaited new Kindle ($360) reflects an evolution, not a revolution. It now holds more than 1,500 titles. (Just try stacking those on your night table.) It displays digital ink in 16 shades of gray, instead of four. That's especially helpful on the eyes, since it now runs 25 percent longer on a single battery charge (more than two weeks when the wireless is turned off). Perhaps most significantly, its buttons have been redesigned, addressing longstanding user navigation complaints. Those long side page-turning bars that people said caused too many accidental page skips? They're now smaller and click inward.

A few minor gripes: The new experimental "read-to-me" feature, which promises push-button audio of anything in your library, works fine if you like annoying robotic voices. And the device no longer comes with a protective case unless you're willing to pay an extra $30. While Amazon designers have oomphed up the numbers and tweaked some bugs, there's nothing game-changing afoot. Still, the Kindle is, for now, the e-reader to beat.