Amazon.com unveiled its Kindle e-book reader last week with a PR extravaganza that might impress even Steve Jobs. Amazon founder Jeff Bezos brandished his first hardware product on Charlie Rose and the cover of Newsweek, and secured testimonials from such dead-tree luminaries as Toni Morrison and Lemony Snicket. The marketing seems to have worked. The $400 Kindle is already enough of a success that, as I write this, it’s back-ordered until Dec. 17.

If you go by the wisdom of the blogs, however, the Kindle is less the iPod of books than the Apple IIc of books. Early adopters have groused about the oversized PREV PAGE and NEXT PAGE buttons, which make it tough to pick up the device without accidentally paging through the book you’re reading. They’ve also sneered at Amazon’s copy protection, which is so crippling that you can’t even buy an e-book for a Kindle-owning pal.

My first six days with the Amazonian e-reader have confirmed that these criticisms are on target. I’d be startled if, at least in the pricey gizmo’s initial incarnation, this is the product that gives e-books iPod-like ubiquity. Still, unless Amazon caves quickly, it will probably be the closest thing to a mainstream e-reader yet. For everything Kindle isn’t, it remains the best attempt so far at making e-books make sense. To borrow the famous left-handed compliment that Alan Kay gave the original Macintosh, it’s the first e-book reader that’s good enough to criticize.

Amazon’s e-reader doesn’t look special from the outside. It’s plasticky, white, and a bit chunky, about the size of a 200-page trade paperback and weighing in at 10.3 ounces. The device’s greatest innovation is hidden inside. Earlier e-readers—including Sony’s svelter, cheaper, still-extant Reader—made you buy your books on a PC and then copy them to the unit via a cable. Kindle, though, has built-in wireless broadband, courtesy of Sprint’s nationwide EVDO network. Preconfigured and provided at no additional charge, Amazon’s Whispernet service lets you browse for e-books and other content on the device itself. You can download a book in seconds anywhere Sprint has coverage.

It’s a remarkably seamless experience, the purest expression of Amazon’s 1-Click approach to shopping. Roaming the aisles of a local Borders with Kindle in hand, I bought and downloaded Elmore Leonard’s Up in Honey’s Room in a lot less time than it would have taken to locate it in the stacks and make my way through the checkout line. I also paid $9.99, rather than Borders’ $25.95 plus tax.

When it comes to book selection and pricing, Kindle is far superior to its predecessors. At launch, almost 90,000 books are available for purchase compared with 20,000-plus at Sony’s online store. That’s puny compared to the millions of volumes that Amazon sells in printed form, and the selection is strongest in high-profile books and public-domain oldies. You can buy 100 of the 112 titles on the New York Times best-seller list, for example, but Vladimir Nabokov and Ian Fleming are both missing in action. On the plus side, almost everything is a tempting $9.99 or less.

Beyond books, Amazon has sealed deals to deliver 11 newspapers via Kindle, including the New York Times ($13.99 a month) and Wall Street Journal ($9.99). Eight print and Web-based magazines (including Slate) are available for between $1.25 and $3.49 a month, as are 300 blogs, for 99 cents or $1.99 apiece each month. Most of this content is available for free on the Web and in some cases via full-text RSS feeds, with better formatting and more interactivity. But Kindle’s approach offers something of the convenience of traditional newspaper and magazine subscriptions. As long as you leave the wireless connection on, fresh content is downloaded silently in the background even if Kindle is turned off, so it’s ready to read when you are.

While Amazon has integrated its hardware and e-commerce services, you aren’t dependent on the company for content. You can e-mail any text document, such as a tome from Project Gutenberg’s free book catalog, to your Kindle for a charge of 10 cents per file. There’s also a rudimentary Web browser tucked behind a menu option labeled “Experimental.” Kindle calls this feature “Basic Web” and cautions that it works best with sites that are mostly text. That’s about right—it’s essentially the equivalent of a middling cell-phone browser, only on a large, monochromatic screen. (There’s no wireless data service charge for surfing the Web or using the Kindle store.)

Like the Sony Reader, Kindle can display images, but it’s fundamentally a text-oriented device. Both machines dispense with LCD in favor of a 6-inch grayscale “electronic paper” display using technology from E Ink Corporation. E-paper draws so little power that Kindle can run for two days with its wireless connection turned on, or for a week with the wireless shut off. And it doesn’t flicker or wash out in the sun—as long as there’s enough light it looks more like paper than an electronic display. (The Sony Reader has a slightly more advanced implementation with slicker typography and eight shades of gray vs. Kindle’s four; the difference isn’t enough to stress over.)

But in an age in which even cheapo cell phones have vibrant color screens, e-paper’s dark-gray-on-light-gray color scheme is drearily retro. The Kindle refreshes much more slowly than any device with an LCD screen, resulting in a perceptible pause and flashing effect as you flip pages. Since the display’s refresh problems preclude even simple animations like a moving cursor, Kindle’s designers have created a workaround—a thumbwheel that moves a cursor up and down a skinny, secondary display to the right of the main screen. To navigate, you point the cursor at menus on the main screen and click to select them. It’s kludgy and a bit primitive but gets the job done.

So, why should you shell out $400 for Kindle when even the most cut-rate printed volume is easier on the eyeballs? As with previous e-book readers, the biggest selling point is portability. I wince at the prospect of lugging even one hardcover on a plane trip, but Kindle can hold the equivalent of 200 in its internal memory, and it has an SD card slot for further expansion. Other conveniences include six text sizes to choose from, full-text searching, annotation, and easy access to the Oxford New American Dictionary and Wikipedia. Most of these features use Kindle’s keyboard, which works quite well, though it adds to the device’s bulk and detracts from its aesthetics.

The proof of any e-book reader’s worth, of course, is in the reading. Here, Kindle proves a mixed bag. I breezed through Steve Martin’s memoir Born Standing Up, reading at least as quickly and enjoying myself at least as much as if I’d sprung for the hardcover. When I flipped the last virtual page, I was sorry it was all over.

But the book’s photographs, crisp and evocative in the printed edition, are barely decipherable on the e-paper screen. And although Kindle contains a welcome letter from Jeff Bezos declaring his goal to have the device “disappear in your hands,” in mine it occasionally behaved like a buggy piece of first-generation consumer electronics. At one point, it inexplicably decided to display the book as center-justified text before abruptly switching back to left-justified format.

For all of Kindle’s rough edges, it’s the first e-reader that’s left me believing that content-consumption tablets could one day be everywhere. My hunch is that they’ll resemble flashy, oversized iPhones more than Amazon’s resolutely bookish device, though. For now, I’m looking forward to spending time with a well-stocked Kindle on my next cross-country flight. The only downside: Unlike any book I’ve ever traveled with, it will need to stay stowed during takeoff and landing.