On the heels of Apple's big education and iBooks event, it's worth taking a quick snapshot of the education publishing industry as it stands today.

Not because the tools announced today will inevitably transform the future of education the way iTunes and the iPhone did the music and smartphone industries — however fun that may be to imagine.

Rather, you simply can't understand Apple's interest in breaking into the education market without at least a little understanding of that market's scope. And you can't understand why Apple's adopted the approach that it has without understanding that market's connection to our wider media ecosystem.

So, first things first.

The biggest publishers in the world today are education publishers.

It's not even close. In 2009, Pearson's Education division alone brought in more revenue than any other book publisher besides number two, Reed Elsevier, whose biggest businesses are Lexis-Nexis and Elsevier Science.

Education publishers dwarf trade presses. Only the top trade press, Random House (itself owned by Bertelsmann) is bigger than Cengage, the little-known education publishing division that Thomson spun off in 2008 before merging with Reuters.

Education publishers are also much bigger than other media companies that attract much more attention. Pearson is far bigger than AOL or The New York Times Company (and much more profitable). In order to find publishers with greater revenue or profits, you have to go up the ladder to companies like News Corp that include global television markets, or retail entities, like Amazon. This makes companies like Pearson too big to ignore, especially when they're willing to partner up.

Education publishers own lots of "little" publishers, too.

On Wednesday, Daring Fireball's John Gruber wondered whether Apple wouldn't go it alone with textbooks and dare the big publishers to follow — similar to how it built up the iPod as the top music player and only then partnered up with labels to sell their catalogs through iTunes.

"I can see how the music labels resent Apple’s rise to dominance, but I can’t see how Apple does," writes Gruber. After all, in Walter Isaacson's biography, Jobs mentions giving textbooks away for free as a way to route around approval by state and local education committees.

"I’m guessing Apple’s pitch to the textbook companies is something like this," says Gruber:

Digital transformation of your industry is inevitable. Here’s our plan; we’d like you to come along for the ride. But if you choose not to, we won’t hesitate to leave you behind.

Maybe Apple did play that kind of hardball, either with all three big textbook publishers or pitting them against each other. But Apple has literally billions of other reasons to play nice.

Let's suppose you don't really care about textbooks. Pearson also owns Penguin, the world's second largest trade publisher. They also own the Financial Times and a 50% share of The Economist.

That's the same Penguin that partnered with Apple to help launch iBooks along with the iPad. And that's the same Financial Times that proved publishers could bypass the App Store's 30% cut and still grow their subscriber base on iPhone and iPad.

Likewise, Houghton Mifflin Harcourt publishes a ton of textbooks — but they also publish The Hobbit and The Lord of the Rings.

Oh, hi, Apple. Do I have your attention now?

Education publishers don't just sell books; they deal in information.

The classic example of this is McGraw-Hill. Besides being the second largest textbook publisher, McGraw-Hill owns Standard & Poor's — a combination publisher, stock index, investment researcher and credit rating agency. This seems less odd if you know McGraw-Hill's flagship publication since 1929 has been BusinessWeek, which it sold to Bloomberg in 2009.

McGraw-Hill kept the most lucrative businesses — textbooks and financial services — and ditched the connective tissue between them. Only now, after scrutiny of S&P's credit ratings, is it planning to divide itself into two separate companies.

We talk a lot about the transformation to an information economy, but companies like Pearson, Elsevier, Thomson Reuters and McGraw-Hill epitomize it. Textbooks and institutional publishing services lie at the exact juncture of knowledge and money.

Every education publisher has invested deeply in the broader education industry — especially its digital future.

Almost all big education publishers are involved in some way with educational testing and learning management platforms. Pearson partners with The College Board to administer the SAT and scores the National Assessment of Educational Progress. The company makes $1.7 billion each year in worldwide educational testing alone.

Every education publisher knows that its biggest growth opportunities are digital products and services, expansion into global markets, and efficient investment in its content-based enterprises (like books and journalism).

Each of them are working on end-to-end solutions: not just textbooks and testing, but software-based learning delivery platforms, much like what Apple unveiled Thursday with iTunes U. They invest in highly interactive platform-specific apps like Inkling, and basic, cross-platform e-textbook standards like CourseSmart. And they invest in Apple.

Their giant size and reach throughout the education and media landscape gives these publishers advantages and disadvantage. One disadvantage: they move slowly. One big advantage: You cannot outflank them.

One after another, Apple, Inkling, Barnes & Noble and other digital publishers have given up trying to outflank academic publishers. Now we will see whether Apple's spotlight can get them to move.