When Amazon and Barnes & Noble announced that they would soon allow e-books (and free e-book sharing) on computers and mobile devices, it sent me into a quixotic tizzy about the future of e-readers. The ability to read e-books on small computers and smartphones fit with the long story of personal technology, which says that once-disparate functions -- music listening, email checking, phone calling, etc -- are eventually integrated into multi-purpose gizmos.

I called this the Swiss Army Knife Theory of personal technology. I wrote:

Today it seems to me that there are at least three major classes of popular personal technology that have yet to be fully consolidated into a modern Swiss Army Knife: cell phones and computers and I think e-readers will soon fill that trio. The arc of personal tech history dictates that functions don't remain separate for very long. Someday the idea of an e-reader designed merely to read will seem as limiting as the cell phone that doesn't receive emails or the desktop that won't fit in your satchel. It will still have an consumer audience, but it will be seen as behind the wave.

The Atlantic's James Fallows responded: Not so fast.

I disagree with the interesting post by the Atlantic Business Channel's Derek Thompson, who looks at the new e-readers and says that we're headed for a Swiss Army Knife-style combination of many different functions in a few all-purpose electronic gizmos. I'm skeptical because of the dozen previous times through the computer era in which that prediction has not panned out. "Real" cameras are still much better than in-phone cameras; the right device to carry in your pocket, as a phone or PDA, will always be worse to read on than a device with a bigger screen, which in turn is too big to fit in your pocket; keyboards are simply better than little thumbpads for entering more than a few words, and any device with a real keyboard has to be a certain size. So, sure, some things will be combined, but the all in one era is not at hand, and won't be.

I agree with everything in bold, and disagree with the underlined sentence. James couldn't be more right that my BlackBerry camera takes pictures that look like cheap Monet prints, and my mother wouldn't read The Poisonwood Bible on her cell phone if Barbara Kingsolver joined her, offered to answer questions about character development, and promised to base her next book on mom's life.

But it seems to me that the all-in-one era is arguably upon us. The iPhone can already make calls, access the Internet, edit documents, acquire thousands of time-saving measures through the App Store, read online news and (soon) legally access full books. The iPod Touch, combined with a portable wireless cloud device like the MiFi, can perform just about all the same functions. Cell phones are even experimenting with E-Ink to reduce to glare and emulate the look of actual books.

To be sure, nothing demonstrates the limitations of the Swiss Army Knife Theory of personal tech as much as the Swiss Army Knife, with its adorably fragile scissors and maddeningly unwieldy corkscrew. So I'm not arguing that some future all-in-one device will replace the need for books, or computers any more than the SAK obviates the Rabbit Corkscrew. Maybe my thesis is perfectly banal: The course of personal technology is centripetal. Things come together.