Big news today: The Boston Globe is planning to launch a subscriber-only website that will coexist with its current, free site. The new BostonGlobe.com, which is currently scheduled to launch in the second half of 2011, will feature premium content, in the sense of both quality and cost. And the current Boston.com — expected to be focused on “breaking news, sports, and weather, from a variety of sources, as well as classified advertising, social networking, and information about travel, restaurants and entertainment” — will become, essentially, a hyperlocal site for Bostonians.

In other words, the Globe is doubling down on, yes, doubling down. Take your mass-market audience and leverage it via a strategy that rewards mass itself: advertising. Then take your niche audience and leverage it via a strategy that rewards audience loyalty: subscription. (BostonGlobe.com, for its part, will likely feature advertising, as well, though the specifics are as-yet undetermined.) Or, as Bob Powers, the Globe’s VP of Marketing and Communications, told me when I spoke with him this afternoon: On the new BostonGlobe.com, “we’ll look more to the consumers to fund the journalism.”

The Doubleminty strategy is, in some ways, simply a logical extension of The New York Times’ soon-to-be-implemented metered paywall system: While the Globe’s sister paper is trying to serve both its broad audiences — the mass/casual and the niche/loyal — with the same property, the Globe is instead serving them by severing them: by creating two different destinations. Today’s announcement is the result, in part, of the paper’s studies of both market research (surveys of both heavy users of Boston.com and the market as a whole) and analytic traffic patterns. “And what we found,” Powers says, “is that there were different audiences: one looking for breaking news, things going on in the city, that kind of thing — and the other looking for the Globe and its high-quality journalism.”

Speaking of that journalism: Who, exactly, will be providing it? The obvious drawback of a site-bifurcation is that it gives you yet another hungry beast to feed. On the paid site, in addition to the content that fills the pages of the print product, there will also be slideshows, interactive features, updates, and other such products audiences have come to want and expect on the web. The thought at this point, Powers says, is that “the same journalists, reporters, and editors will be producing the Globe online that produce the Globe — and generate content for Boston.com — but we haven’t figured out exactly where we need to add online skills and human resources.” And though “we’re prepared to invest in that,” he says, “we want to analyze it a little bit more.”

In part, the double-site plan could be seen as a “retention and switch strategy” for the Globe, Ken Doctor, the Lab’s resident economics-of-news expert, told me: retain current print subscribers by bundling print and digital, all the while preparing for a shift to digital. Many papers’ recent experiments with merged revenue streams, Doctor says, are modifications of the one employed by the Arkansas Democrat-Gazette — one ultimately aimed not at stopping print losses, but simply at slowing them. Newspaper companies still get a whopping 85% of their revenues from their print products (advertising and circulation), Doctor points out — “so if you can even slow that loss as you’re transitioning, that’s a good thing.” (Subscriptions to BostonGlobe.com will come free with the paper’s print product.) And BostonGlobe.com, which is being presented as basically a bells-and-whistles version of the print product, could help with that — while Boston.com “gives them the capability of doing, in an easier way, what everybody wants to do: maintain a robust digital advertising business.”

The double-down’s other potential payoff? A killer app that is, literally, an app. BostonGlobe.com may well represent, Doctor suggests, a middle ground on the way to another, even more removed, destination for Globe content: an iPad or other app. (Thus, the “switch.”) “To the extent that the tablet becomes a switch medium,” he says, “you establish a price that gets reader revenue in the digital world” — allowing for experimentation with, and thus ostensibly the refinement of, pricing architectures. You could read the site bifurcation, in other words, as a stepping-stone strategy: a way to help the Globe navigate toward a more tablet-centric world.

Which, though it could prove rewarding, is also risky. One of the factors hanging in the balance here is also one of the most valuable to a news outlet: its brand. Particularly for the Globe, which has spent years building up its name, there’s the chance that a two-site strategy might solidify into caricatures — The Good Site and The Bad Site — with the latter, in particular, ultimately harming the reputation of the sites’ parent organization. When I asked Powers whether that was a concern during the Globe’s decision-making process, though, his reply was emphatic: “No. In fact, we think that by separating them out, they’re going to strengthen each other — that there will be greater clarity of what each really stands for.” These aren’t two sites, as he puts it; they’re two brands. And that distinction could make a big difference as Globe staffers strategize about the sites’ content — and about the extent to which it will, and won’t, be complementary.

It’s in large part to allow time for such crucial decision-making that the new site’s launch date is set so far in the future. And that’s probably a good thing. The Globe is owned, of course, by The New York Times Company, and the web-bifurcation experiment, however it works out, will have bearing not only on the Globe itself, but also on other metro papers, among them its (big) sister in New York. (By the time BostonGlobe.com is launched, if all goes according to the paper’s much-publicized plans, the NYT will have erected its paywall.) Its results will offer lessons for magazines, too: The National Journal, it’s worth noting — the Great JournoPoacher itself — plans to implement a similarly divide-and-conquer-focused approach to its web presence. So in doubling down, to continue the metaphor, the Globe is betting big. And they know it. “We’ve got a lot of details to figure out,” Powers notes of the new strategy. “But we want to get feedback as we develop it — and test what people want.”