This post comes from Lynn Mucken at MSN Money.

They didn't attract much attention last week, what with The Wedding and The Donald and all that, but there were two developments that will have tremendous effect on the American way of life:

• Amazon.com announced that its e-books will be available for loan to Kindle readers through 11,000 public libraries later this year.
• Advertising for Barnes & Noble's Nook Colorcontained no mention or photos of the book chain's brick-and-mortar outlets.

What does that mean? It means the paper book is on life support, with plans to pull the plug soon, very soon. Here are five reasons why: Post continues after video.

Profit margins. Right now a book publisher has several major expenses: creation (finding good material, paying the author, editing and designing), advertising, production (printing), distribution and paying the middleman (the seller).

• Try the 50-30-20 budget

With an e-book, production and distribution costs instantly drop nearly to zero. Big savings, bigger profits.

 

It would not be surprising to see one or all of the six major publishers try to bypass the middleman entirely by putting out their own line of e-readers. And, of course, the new math on costs could bring the small publishing houses into play.

 

Libraries. As the Amazon.com announcement shows, it was inevitable that its e-books would be available for loan. Three of Kindle's major competitors -- Barnes & Noble's Nook, the Kobo and the Sony Reader -- are already compatible with libraries.

The library market is just too big to ignore, so it is all a matter of negotiating the deal with the libraries and with the publishers. Last month, for instance, publisher HarperCollins imposed a "26-checkout limit" that forces libraries to repurchase an e-book every 26 times a title -- will the term "book" disappear too -- has been loaned out.

Library finances. If you haven't been to your local library branch in the past few years, you might be surprised to learn that there are relatively few books actually there. Nowadays, it is just a transit center. If you want to read the latest James Patterson release, you just go online, click a couple of keys and then wait until the library e-mails you to say the book is available and waiting at your branch.

• Quiz: Estimate your credit score

With local governments hurting for money -- San Diego, for instance, wants to have its branch libraries open just 18 hours a week -- they would be delighted to get out of the business of hauling books all over the place.

Reader costs. OK, the new Nook Color is priced at $249, but black-and-white Nooks are available for $100 less, and e-reader prices, like those for all developing electronics, will drop rapidly.

Even at today's prices, which will probably be cut as publishers no longer have to protect their in-place booksellers, the savings for a two-book-a-month consumer will pay for an e-reader in a hurry.

• How do your finances stack up?

Take for example, The New York Times hardcover bestseller Nora Roberts' "Chasing Fire" and paperback bestseller Sara Gruen's "Water for Elephants."

Online, ordering a paper book, "Chasing" is $15.09 at Amazon and $17.91 at Barnes & Noble. And you may pay shipping costs. E-books cost $12.99 from both companies.

The physical "Water" goes for $8.22 at Amazon and $8.96 at Barnes & Noble, but $4.17 and $6.39 respectively, for e-reader versions. 

Of course, that price will drop to almost nothing -- some libraries are going to pennies-per-day "rental" fees -- if you borrow books. It is likely, however, that there will be waiting lists because libraries will still buy only a limited number of each e-book.

Reader ease. Books are more than just words; they are a way of life. So it is impossible to argue with those who resist e-readers because they "love the feel and smell of books."

However, e-readers are lighter, have adjustable type size and you can take six books on a vacation without taking up valuable luggage space. They open automatically to where you left off, and you can mark sections for rereading. The lighting and graphics improve with each generation. Partners with the same account can share a book without waiting for the other to finish.

The only negative is that book covers, like album covers before them, will disappear. But mourning that loss of icons will not keep you from reading.

Will the paper book disappear as quickly as film collapsed under the onslaught of digital? The numbers above indicate the transition will come quickly, but paper books and a niche industry will survive -- you can still find record stores hidden away -- for those who will not change or simply embrace nostalgia.

 

More on MSN Money:

• Why you shouldn't buy a Kindle
• Kindle ads: Great idea or horrible nuisance?
• Report: E-book sales to quadruple
• No one loves Barnes & Noble
• E-book sales jump past hardcover