Khosrowshahi, who was speaking at the Goldman Sachs Technology and Internet Conference 2010 in San Francisco, says Expedia would like to give HomeAway some competition, and Expedia may be able to do so because it sees great potential in two TripAdvisor listings’ businesses: vacation rentals through FlipKey, and Business Listings of bed-and-breakfasts and hotels.

“Listings, for us, is a really interesting business,” Khosrowshahi says. “It is a whole new revenue model.”

It’s interesting that Khosrowshahi envisions competitor HomeAway going public, while he all but ruled out an IPO for TripAdvisor a few weeks ago.

Of course HomeAway and TripAdvisor find themselves in disparate situations.

Homeway is an independent, privately held company, which is funded by Austin Ventures, Institutional Venture Partners, Redpoint Ventures, Technology Crossover Ventures and Trident Capital.

In contrast, TripAdvisor is a subidiary of public company Expedia Inc.

How valuable is TripAdvisor to Expedia?

Khosrowshahi says TripAdvisor’s EBITDA (earnings before interest, taxes, depreciation and amortization) margins are “well north of 50%” and they come in at that number “despite aggressive investments across the globe.”

The Expedia Inc. CEO says TripAdvisor’s margins are superior to those of metasearch companies and other travel players because TripAdvisor provides “higher-qualified” leads to advertisers, who are willing to pay more for them.

In addition, TripAdvisor attracts much of its traffic organically — meaning for free.

Khosrowshahi called TripAdvisor’s margins “spectacular.”

There is no debate about that.