In the last week, Amazon announced two tweaks to the way the company works with publishers and software developers for its Kindle electronic book reader.

I'm sorry, did I call it an ebook reader? It's now a platform, not a single-use device. For all of Amazon's insistence that the Kindle was designed to serve one purpose best, it will now be serving many masters.

Why now? Apple is widely expected to introduce a super-sized iPod Touch on January 27 at a press event that yours truly will be at. The tablet or slate or flat computing device or whatever will likely offer full-screen, full-motion video and run iPhone apps. Apple has apparently been meeting with book, newspaper, and magazine publishers to strike deals to include content for its new device, and Amazon is clearly running scared, pooping out press releases to remind the world that the Kindle is out there.

Until now, Amazon's Kindle relationships with publishers (whether media or book) has been strained, even though many content firms have licensed titles and subscriptions to Amazon. Amazon reportedly takes 70 to 80 percent of the revenue from magazine and book subscriptions, which is why you will pay $15 per month for automatic Kindle delivery of the Wall Street Journal, for which far more extensive web access costs just $100 a year, or about $8.50 a month. Many publications simply don't offer Kindle subscriptions.

Book publishers have had it better, charging Amazon a typical fee of 50 percent of the cover price of the cheapest currently available print edition of any book. (Bookstores typically pay 40 to 60 percent of a book's cover price). If HarperCollins sells a new book for $36 in hardcover, Amazon pays them $18, and sells it for $10. How does Amazon make money at that rate? I'll tell you: volume.

No, seriously: It's because most of the books Amazon sells for the Kindle are sold at a price that makes Amazon plenty of money. The profit margin on most books Amazon sells subsidize its current underwriting of new "hardcover" releases, which the firm uses as a tool to get the kind of reader to buy a Kindle who wants to buy new hardcover fiction books.

Publishers hate this, even though they make the same money regardless of what Amazon charges. Publishers believe that Amazon is attempting to increase price sensitivity—make book buyers less and less willing to pay more—for new hardcover books as a way to force publishers to lower license fees. Some publishers have delayed or planned to delay Kindle availability of new novels for days or months to preserve hardcover prices. (Amazon, by the way, sells Dan Brown's The Lost Symbol at 60 percent off list price in hardcover as part of an insane price war with Walmart.)

In contrast, Apple's deal with software developers for the App Store, the application marketing and delivery part of the iTunes Store, is a 70-30 split in favor of developers. Most developers haven't found this split horrible, because many pay ordinarily 5 to 15 percent in fulfillment fees for online purchases of desktop OS software that they sell on their own sites. Apple builds that 5 to 15 percent into its 30 percent cut. There have been many complaints with the restrictions on what Apple allows in the App Store, but developers generally seem to find the price split to be acceptable.

Amazon fears that Apple could be making a deal for the same kind of 70-30 split with publishers, which is likely why the bookseller added a new kind of revenue split with an ocean of provisos attached a few days ago. These terms currently only apply to small publishers and self-published authors who use a Kindle "self-serve" system to add books for sale.

Amazon will give publishers that identical 70 percent of revenue (minus a few pennies in wireless delivery charges) in exchange for the publisher agreeing to price the book between $2.99 and $9.99, price it 20 percent or more below any print edition, and let Amazon sell it in all areas of the world where the publisher has rights.

Print publishers offer authors relatively terrible royalties for ebooks. Authors, if they're lucky, might get 15 percent of the list price of an ebook, versus the 70 percent Amazon is offering.

Amazon's deal might make sense for authors who control the electronic rights to their works, or who might want to make different deals for future books. Amazon will restrict the top list price of a title in this program to $10, but 70 percent of $10 is $7. An author in a traditional publishing relationship might get 15 percent of the $20 to $30 list price that the publisher bases electronic licensing fees on--which is $3 to $4.50 to the author. The math seems obvious.

The change to the revenue split moves Amazon far more closely into the role of a publisher. But it's hard to read the company's actions as anything but reactionary, hoping to instill in publishers the idea that Amazon could pay more before Apple unveils its own 70-30 split.

Amazon also played up its fear of the tablet by announcing an upcoming beta of a developer kit for software programmers to build applications for the Kindle. Until now, Amazon has only offered a few features on the Kindle, including an "experimental" Web browser.

This new option allows free, paid (one-time fee), and subscription apps, with a 70-30 split in the developers' favor for apps that involve fees after download charges of 15 cents per MB are deducted. A 10 MB program would cost $1.50 in download fees that the developer would absorb from the program's price, for instance. One-time fee apps can't use more than 100 KB of data each month, while subscription apps will be charged based on use.

This all seems a little baroque, and a little too late. Developers have already produced more than 100,000 applications for the iPhone OS platform, used for both iPhones and iPod Touch players. (The iPod Touch has only wi-fi built in and lacks a camera; iPhones outsell iPod touches by about 3 to 2.)

The Kindle in every model has a battery-kind, high-contrast black-and-white screen and a keyboard. Apple's tablet, as I mentioned earlier, will likely look and act like a full-color larger version of the iPod Touch. (It's unclear whether there will be a cell-network linked tablet, or just one with wi-fi.)

Apple has sold tens of millions of iPhone OS devices worldwide; Amazon perhaps a million Kindles, mostly in the United States so far due to limitations in licensing and cell network arrangements.

Amazon enters this potentially disastrous fray with what will certainly be less-expensive devices, a built-in existing user base, a library of hundreds of thousands of books, and a  direct customer base of tens of millions of people who interact with its Web site.

On the other hand, retail analysts and electronics store operators were convinced that the retail Apple Store would be a massive failure, and handset makers and cell companies thought the iPhone would be a laughable entry with no traction. Today, Apple stores take in more per square foot than Tiffany's.

Amazon ought to be worried, except there's one footnote. Amazon offers Kindle software for Windows, iPhone OS, and the BlackBerry platform (a Mac app is "coming"). Any book purchased on any device or computer or via the Amazon Web site can be retrieved and read on any other device registered to the same Amazon account.

If Apple succeeds in creating a tablet that supplants the Kindle hardware, Amazon still has the potential to be one of the major sources of books to Apple tablet owners.