Stealth startup CircLabs launched in late May with the goal of “sustaining” the business of journalism by bundling content, social features and ads, while giving readers a single platform for subscriptions and micro-payments to multiple publications. Now, EVP Martin Langeveld offers some details on how the company plans to do it: with a browser add-on that pulls in users’ surfing data—along with any other info they choose to feed it—then offers content and advertising recommendations accordingly.

Dubbed Circulate, the product will let readers create personalized start pages and set up e-mail alerts; CircLabs also plans to make a mobile app available (like the Journal’s iPhone app pictured here) from the onset. The company (a spin-out from the Donald W. Reynolds Journalism Institute, or RJI), calls Circulate a “personal information agent,” since it will learn a user’s content preferences over time and then let them share it over various social networks.

CircLabs is betting that people will want the convenience of a one-stop content hub that “knows” what they want to read—instead of having to sift through multiple sources (RSS feeds, e-newsletters and visiting sites, for example). The big hurdle is getting enough people to take the first step, submit their info, and then actively use Circulate.

Circulate will also only be as good as the publishers that agree to let it pull in their content, but CircLabs says there are a number of reasons for big news organizations (and indie blogs) to become partners:

—Local ads: Users sign up to get geo-targeted content, meaning Circulate can run local, contextually-targeted ads

—Subscription revs and per-article payments: Circulate’s content suggestions can include subscription-based articles, as well as news clips that readers can choose to pay for individually

—Affiliate sales and lead generation: Once the service gains traction, CircLabs plans to offer product and service recommendations, coupons and surveys; it will share any lead-gen and affiliate sales revenue with the publisher

The company says Circulate will launch in phases; the beta launch is scheduled for this fall. With the Feds promising to lay down laws around behavioral targeting around the same time, it remains to be seen whether the new legislation will hamper the growth of similar browser-based services. Langeveld told us CircLabs plans to “comply with any targeting regs, and even without them, we’re going to be very clear and very explicit to users about what we track and allow them to opt in or out of it.”