Among the hundreds of professional blogs started six years or so ago, exactly two (so far) have sold for hundreds of millions of dollars: Huffington Post and, as of yesterday, Bleacher Report. But in the flurry of announcements about Bleacher Report’s deal with TimeWarner, few seemed to notice the other telling similarities between the two properties.

The first is that they were both backed by the same guy: Fred Harman of Oak Investment Partners. Oak is a growth investment fund not particularly known for dominating the Web 2.0 world. But Harman has carved a lucrative niche in media — an area that most investors run screaming from, because it doesn’t scale like tech companies and, with the exception of Huffington Post and Bleacher Report, there haven’t been many nine-figure outcomes.

Most of Harman’s hits have been on the ad side, including Demand Media, aQuantive, Fastclick, and a pending bet on John Battelle’s ad network, Federated Media. So while his two wins on content are surprising, it’s not a surprise that the two sites he backed both had a similar playbook. Both sites relied heavily on a mix of paid, professional bloggers and an army of people content to blog for free.

As a professional journalist, part of me finds this incredibly depressing, the idea that the only way to build a blog worth more than $50 million is to let the unwashed masses onto your CMS? Isn’t that just further dumbing down the news?

Not necessarily, when done well. The key with both Huffington Post and Bleacher Report wasn’t an implicit belief that crowds were wise, rather it was their ability to use them wisely.

Huffington Post bifurcated its site between very high end content — celebrities who didn’t blog anywhere else, and more recently very highly paid poaches from organizations like the New York Times– and the rest. Pulitzer Prize material and photos of kittens. The two might seem like they don’t belong on the same site. But having high notes and low notes, is far more effective (and only half as soul crushing from a journalism point of view) than a site that maximizes just for the middle of the spectrum– which is far more common in professional blogging.

BleacherReport leveraged sports enthusiasts differently. It vetted and approved people it would let write for it and had far fewer of them. It aimed for the long tail — covering teams and sports that national news organizations didn’t care about, rather than SEO-dream stories on the big names. But another key for BleacherReport was that, unlike political blogging, almost no one else was paying attention to sports.

Astoundingly, the biggest online sports verticals still came from the old guard: CBS Sports, Yahoo, Sports Illustrated, and ESPN. That’s the biggest reason Harman backed the company back in 2011. “Sports is a big opportunity, and no one has gotten it right yet,” Harman said in an interview with me at the time. “People are clearly as passionate and opinionated as they are in politics, and they are less inhibited to express their opinions. I’d argue Bleacher Report has done a far better job of embracing the capabilities of the online medium than the big sports name brands have.”

Hobbyist bloggers were willing to write for free, because they were the same guy who talks your ear off in a sports bar. They simply want to be heard. BleacherReport gave them the resources of a big news organization — including readers. The only thing it lacked was a paycheck.

This approach isn’t bulletproof. A user-generated blog about, say, accounting wouldn’t work. Likewise, a blog about kittens wouldn’t either, because, while adorable, kittens aren’t particularly divisive. Politics and sports are topics where have polarizing opinions and love to rant, so much so that they don’t mind ranting for free. And in many cases, a smart bystander that doesn’t happen to be a reporter, has just as good insight as someone paid to commentate from the sidelines.

That’s particularly the case with sports. I’d argue that someone who watches a team everyday and devours the stats about them has most of the ammo of a paid-sports writer. Sure, they don’t get access to the locker room. But I’m not convinced a scrum of journalists shoving microphones into an athlete’s face after a perfect game really yields special insight.

Indeed, I have read better posts about my favorite team — the Oakland A’s — on BleacherReport than I have on most mass-sports sites. Partially, because die hard fans are the only ones who really care about small market teams like the A’s.

Despite a similar way to create content, BleacherReport and HuffingtonPost had very different traffic patterns. Huffington Post got its nine-figure-valuation by a sheer onslaught of traffic and page views, thanks to carefully honing every page view-generating and SEO tactic in the book. But BleacherReport edged towards a $200 million price with just 10 million monthly uniques, according to comScore. (They claim more like 40 million off of internal numbers.) comScore lists TechCrunch at around four million uniques. (Internal numbers at the time of the sale were a lot higher as well.) And at a reported $175 million– which we’ve subsequently heard was actually closer to $200 million– BleacherReport got far more than double TechCrunch’s sub-$30 million exit.

So why did BleacherReport seemingly get an extra zero on its valuation?

It’s surprising, to me at least, that the wins in sports and politics have so far dwarfed the exit of any tech blog. Sure, there are the persistent rumors that CNN is buying Mashable for $200 million. Those rumors have come and gone a few times, and never turned into a deal. But one thing is clear: Those rumors only get more credible (and the price tag higher) the further Mashable gets from being a tech blog and more it gets into other verticals. An advertiser on several tech blogs recently told me that Mashable reps told him they were more likely to build a sub-verticle for cars than developers at this point. Business Insider too has pivoted far from its early tech blog roots– and on any given day there’s more about boobs than business on the site.

Technology was one of the canaries in the coal mine of blogging, since the people who wanted to write about it and read about it were inherently all early Web and new media adopters. One reason may be that technology blogging was hit with so many entrants that it became hopelessly fragmented in terms of advertising, events revenue, and attention. But another may be that no one has wisely used crowds in the tech world to power content the way HuffingtonPost and BleacherReport have.

This is not something that PandoDaily is likely to do, for one simple reason. It’s not that I have a snobby, philosophical objection to it. It’s because we are more of a news blog than a product blog.

Some business sites have tried to follow this playbook by allowing just anyone to blog, but most do it wrong. (Oh, hey, Forbes.) The key is inviting people to write about topics where a smart spectator’s opinion matters just as much as an insider. When you are writing about things like breaking news or the inter workings of a company, its not really opinion-based journalism. There is largely a single truth that bloggers and reporters are seeking. Is this deal happening? Is the company going under? Why did this CEO oust his co-founder?

Even commentary about, say, whether a CEO should be fired, needs to be backed up by accurate facts, or the argument falls apart. When you are dealing with things as complex as what is really going on inside a company, having deep domain expertise, historical context, and a rolodex of sources who can tell you what is really going on are pretty material to getting to that reality of what is happening and what people need to know. In 15 years of covering entrepreneurs, I’ve found — particularly with startups — that the most likely explanation as seen from the outside is almost never the actual explanation.

But there’s an obvious area of tech blogging that is ripe for a BleacherReport-like approach: Gadget and software reviews. Closely watching two baseball teams gives you almost everything you need to know to have an opinion on who would have an edge in the playoffs. The stats are totally transparent, so the better writing and better analysis is what wins. That’s similar to specs on gadgets, and features and UI on apps and websites.

Sure, Walt Mossberg gets paid $1 million to do reviews for a reason, but there is only one Mossberg. Most of the newer generation of product bloggers — think John Gruber or MG Siegler — didn’t come from a journalism background and many eschew the typical rules of reporting. Those guys have wisely found ways to make piles of money writing their views. But their DNA is closer to an unpaid blogger than a traditional reporter. Indeed even Mossberg is located in Washington DC and not Silicon Valley, because he wants distance from the insiders, so that he’s championing the consumers.

My guess is there’s a nine-figure tech blog to be built empowering an army of next generation Grubers, Sieglers and Mossbergs. And I’m also guessing that done well, Fred Harman would fund that blog.

[Image courtesy ElectronicFrontierFoundation]