NEW YORK  More than four months after Amazon.com released the Kindle, no one is sure whether the latest e-book reader is really hot — or not. But publishers believe that the Kindle has helped, if not revolutionized, the tiny electronic market. Amazon.com has received extensive media coverage since unveiling the Kindle on the Monday before Thanksgiving and announcing that the first run had sold out within a few hours. Amazon.com has declined to give sales figures for the Kindle — at least 2,000, judging from the number of customer reviews — but has said repeatedly that supply is not keeping up with demand, with the device often out of stock. Publishing officials are reluctant to discuss sales figures, but say that they have seen double digit increases in e-book sales since the Kindle's release, including renewed interest in downloads on the Sony Reader. Sales for the most popular books are in the hundreds, comparable to the number for the Sony, which came out in 2006. "The Kindle has increased awareness. Publishers have told me that in some cases the Sony numbers were double or triple to what they had been," says Michael Smith, head of the International Digital Publishing Forum, which tracks e-book sales. Selling through Amazon.com for $399, Kindle is thinner than most paperbacks and weighs 10.3 ounces. It can hold some 200 books, along with newspapers, magazines and an entire dictionary. The Kindle has been praised for its selection, more than 100,000 books, blogs and newspapers, and for the speed of delivery, less than a minute. Fans include such authors as Nobel laureate Toni Morrison, Michael Lewis and Neil Gaiman. In a review last November, AP technology writer Peter Svensson called the Kindle in "some ways an amazing device," citing its full-alphabet keyboard and "rudimentary Web browser that allows you to surf for free." But he also noted several flaws, including "its poor battery life, making it hard to see it as a game-changer." Publishing is older by centuries than the music and film industries and its form of communication, the paper text, has proved far more durable than the vinyl record, eight-track tape or videocassette. New technologies, from the compact disc to the DVD, are usually more convenient and more effective than the ones they replace. But no e-book device has approached the practical and aesthetic appeal of the traditional book. "Books themselves are very efficient machines, and the experience of holding a book is part of the book culture," says Farrar, Straus & Giroux publisher Jonathan Galassi, who called the Kindle "flimsy" and said it reminded him of an Etch-a-Sketch toy. "E-books are a growing niche for now," Smith says, "but I certainly don't see a time when everybody will be reading them. People just love what the traditional book represents to them." E-books undeniably are growing. According to the International Digital Publishing Forum, sales have risen steadily over the past six years, from around $6 million in 2002 to around $33 million in 2007. Those numbers do not include many smaller publishers, or library and educational purchases, making it likely — Smith and others believe — that the market for downloads is at least two or three times larger. Each advance inevitably leads to speculation about a post-paper world: Would bookstores become obsolete? How would publishers handle online piracy? Would authors, like some musicians, become their own bosses, bypassing the industry altogether? E-books have been around for more than a decade and speculation peaked in 2000-2001, the height of the dot.com boom. Several publishing houses set up e-book divisions, and an annual e-book prize, a $50,000 award co-sponsored by Microsoft, was started. Even Barnes & Noble formed its own e-book line, launching the brand with an original work by Dean Koontz. The electronic future, bookseller Michael Powell of Powell's Books said in 2000, was "coming down the road at lightning speed." Few are so bold anymore. Even after tripling their reported sales, e-books are less than 1% of the $35 billion publishing business and likely to remain so. The e-book divisions have been shut down, the e-book award no longer exists. Barnes & Noble has abandoned the e-book field. "The market is very narrowly confined, to New York and Seattle and to a few people who travel and read a lot," says Frank Daniels III, chief operating officer for Ingram Digital, a leading e-distributor. "The Kindle is certainly an important next step, but I don't think it signifies the end of the evolution," Smith says. "It's all incremental, one step that takes place down the line, like in the audiobook industry." E-books have made their greatest progress with their first audience: publishers. For years, publishers resisted the product they were supposed to be pushing. In a 2001 interview, the head of the Association of American Publishers, Patricia Schroeder, rolled her eyes when asked about e-book devices: "I just look at these things and they're fine, but I just think ... " In a recent AP interview, Schroeder spoke favorably of e-books, but said she still had not read one. Public sightings of e-books remain rare compared to iPods or iPhones, but e-book readers have caught on in the industry. The Hachette Book Group USA, Simon & Schuster and Random House, Inc. are among those using Sony Readers (which sell for $299) to review manuscripts and executives are far more likely to say they've read an e-book. "It's not a conversation I'm having with people outside the industry, but I think people will increasingly use e-books. They'll be a niche, like audiobooks. I think that's the best comparison," says Jonathan Karp, publisher of the Hachette imprint, Twelve. "I actually read in bed with the Sony e-reader, and I love it. It's lighter than a regular book, and easier to turn the pages than with a manuscript. I don't have to lug books back and forth. I'm saving paper. It's wonderful." Copyright 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Enlarge Amazon.com via AP file The Kindle will allow downloads of more than 90,000 book titles, blogs, magazines and newspapers. Publishers believe the Kindle has helped, if not revolutionized, the tiny e-book market. Conversation guidelines: USA TODAY welcomes your thoughts, stories and information related to this article. Please stay on topic and be respectful of others. Keep the conversation appropriate for interested readers across the map.