As a new era of media mergers and acquisitions unfolds—in the aftermath of the federal approval of the Comcast/NBCU deal—AOL’s $315-million purchase of Huffington Post ought not come as a surprise.

Media companies, old and new, are rethinking and repositioning in order to grab pieces of a future that will be more digital and less analog, more dynamic and less ponderous, more opinonated and less obsessed with a balance that never was achieved. But this is about a lot more than AOL and Huffington Post. Indeed, it’s about a lot more than media companies and their millions—make that billions. This deal and arrangements like it approach fundamental questions of producing journalism when traditional sources are revenue are drying up, and go to the heart of much broader debates about how citizens will get the information they need to engage in a democratic process that is now far from functional.

Huffington Post, with 25 million monthly visitors, seems to “get” the new age. And AOL, now delinked from the Time-Warner omnibus, is looking to brand itself as the content source for news junkies in a twenty-first century that will have fewer newspapers and traditional broadcast news sources and more digital destinations. It’s been a struggle, and AOL has lost a lot of money in recent years. The company was looking for a bold move.

So, now, AOL CEO Tim Armstrong says he’s cut the deal with Arianna Huffington — editor-in-chief, co-founder and “face” of the popular news and opinion site—and her team in hopes that the the arrangement “will create a next-generation American media company [that] will embrace the digital future and become a digital destination that delivers unmatched experiences for both consumers and advertisers.”

That’s the sort of thing media moguls say when they acquire a “media property.”

But Huffington Post is not just any media property. It’s a place where prominent progressives blog and where millions of Americans get news, information and ideas that tend toward the left.

So is Huffington Post still going to be Huffington Post?

Huffington, whose conversion from conservative commentator to outspoken critic of the Bush-Cheney administration made her a hero with much of the left, says things will stay the same. And her new position, as president and editor-in-chief of AOL’s “The Huffington Post Media Group”—which will take in all of AOL’s content sites, including Patch, Engadget, TechCrunch, Moviefone, PopEater, MapQuest, Black Voices and Moviefone—should give her the authority to maintain her vision.

But the pressure will be on to generate revenues—the great challenge for web-based news operations. Huffington Post reportedly made $31 million last year, which is a lot of money, but not nearly as much as will be expected from an entity for which AOL just paid more than ten times that amount. So Huffington’s marketing skills, which are considerable, are already very much on display. “Our readers will still be able to come to The Huffington Post at the same URL, and find all the same content they’ve grown to love, plus a lot more—more local, more tech, more entertainment, more finance, and lots more video,” she says.

The more reassuring message actually came in a memo to Huffington Post bloggers that was sent Monday morning.

It read:

“We are writing with some very exciting news. As you will see if you click on the HuffPost home page, The Huffington Post has been acquired by AOL, instantly creating one of the biggest media companies in the world, with global, national, and local reach—combining original reporting, opinion, video, social engagement and community, and leveraged across every platform, including the web, mobile, and tablets.

“Central to all of this will be the kind of fresh, insightful, and influential takes on the issues of the day that you and the rest of our bloggers regularly deliver. Our bloggers have always been a very big part of HuffPost’s identity—and will continue to be a very big part of who we are.

“When the Huffington Post launched in May 2005, we had high hopes. But we would have been hard pressed to predict that less than six years later we would be able to announce a deal that now makes it possible for us to execute our vision at light speed.

“The HuffPost blog team will continue to operate as it always has. Arianna will become editor-in-chief not only of HuffPost but of the newly formed Huffington Post Media Group, which will include all of AOL’s content sites, including Patch, Engadget, TechCrunch, Moviefone, PopEater, MapQuest, Black Voices, and Moviefone.

“Together, our companies will have a combined base of 117 million unique U.S. visitors a month—and 250 million around the world—so your posts will have an even bigger impact on the national and global conversation. That’s the only real change you’ll notice—more people reading what you wrote.

“Far from changing the Huffington Post’s editorial approach, our culture, or our mission, it will be like stepping off a fast-moving train and onto a supersonic jet. We’re still traveling toward the same destination, with the same people at the wheel, and with the same goals, but we’re now going to get there much, much faster.

“Thank you for being such a vital part of the HuffPost family—which has suddenly gotten a whole lot bigger.

“All the best, Arianna, Roy, David, and the HuffPost Blog Team”

So what’s the bottom line? It’s reasonable to trust Arianna Huffington when she says she wants to build on the strengths of Huffington Post. It’s also reasonable to trust the Wall Street–insider analysis that says: “Of course, if AOL does try to soften the strident talk, then HuffPo suddenly diminishes in value. Its readers love it because they’re getting what they want—a strong, outspoken force to counter the well organized and well funded conservative movement in the media.”

The struggle in the months and years to come will be to strike a smart balance between bottom-line, journalistic and, yes, political demands. That’s never easy. The history of big-budget online news and opinion ventures includes more stories of failure than success—as Bob McChesney and I detailed in our book, The Death and Life of American Journalism: The Media Revolution That Will Begin the World Over Again (Nation Books). But as we noted in the HuffPost section of the chapter on new media: “While Huffington is sometimes portrayed as being out to strangle newspapers—a prospect that a New Yorker cartoon famously portrayed—she is in fact a passionate believer in journalism who thinks she might yet be able to teach newspapers how to save themselves, most likely on the web rather than in print, but Huffington is not the sort to rule anything out. And in a moment when newspapers are cutting, she’s hiring.”

Huffington said when we were writing our book: “All of us increasingly have to look at different ways to save investigative journalism.”

If, with AOL’s resources, she is able to hire more, if she and her team are able to produce more serious content and if they can identify some of those “different ways to save investigative journalism,” it is possible to imagine that the AOL–Huffington Post deal could mark a turning point in the debate about the future of journalism. That’s a lot of “ifs…”

Huffington’s challenge, a huge one, will be to remove the uncertainty and create a pro-journalism, pro-democracy digital future that is dramatically different, and dramatically better, than what big media combinations have produced up to now.