Flock, a “social browser” eagerly awaited by the tech set, was publicly available this week, after the company by the same name discovered its software had been posted on a file-sharing network.

Built on the open-source Mozilla Firefox browser, Flock bakes in social web services like blogging, photo-sharing, and bookmarking, sparing users the hassle of installing extensions or using multiple applications. The company plans to make money by referring users to companies that offer these services as well as to search engines and e-commerce sites.

The “developer preview,” a pre-beta version of the browser, was set to come out early next week, said Flock founder and CEO Bart Decrem. However, late Thursday, after an early tester made Flock available on a file-sharing network and people started blogging about it, the Palo Alto, California-based company rushed out its browser.

“As an open-source social browser, we really want to engage our users’ feedback and intellect as we develop the features of Flock,” said investor and board member David Cowan of Bessemer Venture Partners. “This isn’t like a new iPod that you can develop behind closed doors, and then ship to the public on the day you announce it. It’s a work in progress.”

The current release includes features such as a built-in blog editor, feed aggregator, and search history analyzer. It also comes with a blog-posting tool that integrates photos and formats and properly cites a highlighted portion on another site so it can be quoted.

Flock combines in-browser favorites with social bookmarks, which dog-ear web sites for later viewing or for others to see. However, the current version lacks key features, such as importation of bookmarks from other browsers, and syncing bookmark collections across multiple computers. It also only offers certain service vendors. The consumer beta isn’t due until December 15.

Refining the Plan

The 14-employee company, founded in November 2004, was formerly called Round Two. Incorporating Mr. Decrem’s experience at the nonprofit Mozilla Foundation, which develops Firefox, the original intent was to build Firefox extensions. Extensions are downloadable improvements to the browser that do things like block ads and track the weather.

After meeting with Mr. Decrem and Flock co-founder Geoffrey Arone, Mr. Cowan said, “I suggested if they were more ambitious, we would be really interested in working with them.” Thus, a browser company was born.

“We’re trying to really nail a problem for a very specific audience—for bloggers, for people who spend all their day using services like [Yahoo’s photo-sharing service] Flickr,” said Mr. Decrem.

But that’s not a huge market. Even if Technorati tracks over 19.8 million blogs, and other estimates put the total worldwide number of created blogs at over 100 million, blogs are still a small portion of the overall web, and bloggers a small portion of the global population.

Barb Dybwad is one of those active bloggers and Flickr users; it’s actually her job, as the author of Weblogs’s Social Software Weblog, now owned by AOL. She says Flock fills some of her immediate needs.

“Right now there’s still somewhat of a gulf between your browser, which is still a desktop application, and applications and services on the web,” she said.

“Firefox extensions start bridging that gap,” added Ms. Dybwad. “[But] people like my mother, for example, are just not going to be installing extensions…. Everyone is going to come to need, or certainly crave, both the level of web integration and customization that a browser like Flock provides.”

And that’s what Mr. Decrem is betting on. As the social applications of the web become mainstream, he said, “It puts us on a path where we’re going to be relevant to tens of millions of users over time.”

Partners in Business

But that first million is all he needs, said Mr. Decrem, to keep the company running, because search engines and other sites are willing to pay for referrals. Flock includes a nod to Google—text typed in the URL bar performs an automatic Google search and points the browser to the top result. There’s also a Yahoo component, with a search box that defaults to Yahoo built into the top right corner.

Those functions generate revenue based on users clicking on the search engines’ contextual ads. Flock will also earn money from directing its users to partner services, for example Flickr or Six Apart’s blogging service TypePad, or through affiliate programs like Amazon.com’s.

And those relationships are enough to be a viable business model, contended Mr. Decrem.

“Simple things like search box alone are enough to keep a browser alive, once it’s got a million users…. If a year from now we have 1 million active users, that will be mission accomplished for us.”

He points to Opera, another browser company, which was recently able to make its browser free by partnering with Google (see Opera Browser is Now Free). The Mozilla Foundation, reportedly due to the same income, formed a for-profit subsidiary in August (see Mozilla for Profit).

Too Much Hype?

The company had spoiled its own plans to operate in “stealth mode,” revealing its product in blog posts and frequent conference presentations. By this week, about 50,000 people were still on the private beta waiting list, said Mr. Decrem.

Initial reviews on Slashdot and tech blogs charged the browser had been over-hyped. Slashdot contributor “superultra” wrote, “They screamed before they had anything… and whipped up the blogosphere in orgasmic anticipation.”

Flock has also faced other criticism, much of it questioning the decision to build a for-profit product based on Firefox. Though Mozilla’s year-old browser is still hovering below 10 percent market share, it is seen as the first browser since the old Netscape to pose a challenge to Microsoft’s Internet Explorer. And Firefox already has a healthy ecosystem of extensions that will have to be modified to work with Flock.

Mr. Decrem’s “tens of millions of users” sounds doable, considering Firefox crossed the 100-million mark last week (see Firefox Marks 100M Downloads). But will those users be siphoned off from Firefox? Mr. Decrem danced around the question, saying, “some users will come from IE, some of them from other browsers.”

On his blog, Mr. Decrem defended his company’s choice to create a browser rather than a set of extensions. “We want to be able to offer our users a complete end-to-end user experience, including a single browser download, an update service, technical support… the works,” he wrote. “Further, we don’t want to break anyone’s Firefox experience, or have our browser break, due to updates either way that have not been fully tested [or] propagated.” He said that Flock would not “fork,” or break away from, the Mozilla code-base, and would release most of its own code.

Mozilla did not respond to a request for comment.

Besides Mr. Cowan’s firm, Catamount Ventures and angel investors provided initial money, and contributed to a recent first round of an undisclosed amount. The list of angels has now grown to include Michael Tanne, Stratton Sclavos, Joe Kraus, Josh Kopelman, and Gil Penchina.