While being part of a private company does afford Conde Nast’s Portfolio a greater degree of flexibility in building its business, the company is nevertheless stressing its ability to grow ad revenues quickly. David Carey, speaking to Jack Myers Media Business Report, estimates that about one-quarter of Portfolio’s total ad revenue will come from its site this year; he expects that share to rise to 30 percent in 2009.

Carey maintains a degree of selectivity when it comes to choosing the advertisers Portfolio wants to attract. There’s an emphasis on the standard ad categories for a general business pub—finance, BtoB, corporate branding, tech, cars, consumer electronics and real estate— while Carey is also emphatic about downplaying typical Conde Nast marketers such as those in retail and luxury.

In terms of offering a timeline for the magazine and website to become fully viable, Carey offers a glimpse at what its five-year plan might take: “Would we spend $100 million over five-to-six years for the print and digital operations? Sure, that’d be a great deal.”

Portfolio.com’s more immediate plans involve creating apps for the forthcoming Google (NSDQ: GOOG) OpenSocial system, as well as Facebook. Those projects are being headed by Ari Brandt, the site’s GM. Brandt also promises to develop a “unique video strategy,” though he doesn’t offer any hints as to what that might entail. Lastly, Brandt and Carey plan to add more bloggers and columnists, such as Howell Raines, the former NYT editor, who will start covering the national elections in March.

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