A well-used passport gives you street cred in the traveler community. A tattered cover and pages filled with entry stamps tell a story of adventures from around the world, and backpackers love to have pissing contests over how many countries they have been to.

A startup called ZeTrip is playing on this dynamic of friendly one-upmanship by creating social travel infographics for it users.

Zetrip is launching in public beta today. It’s a travel site that mines its users’ social networks for posts, pictures, and other evidence of excursions to create a travel profile of their social graphs. In essence, it creates a collective travel log of your online social network.

Ever wondered how many of your friends have been to Australia? What percentage of your friends were born aboard? What are the top countries your friends have visited? The profile contains the answers to these questions, as well as photo galleries and interactive maps.

On the site, you can browse through your friends’ photos, find out which of your friends have been where, and build a destination wishlist and scrapbook. Zetrip estimates that the average member will have access to 40,000 travel photos. Apparently in the private beta alone, Zetrip created 1.5 million travel profiles, with more than 150 million travel photos.

“Last year I was planning a trip to the Galapagos and wanted to find out which of my friends if any, went there, look at their travel photos and ask them for tips or advice,” said founder Edouard Tabet. “This information was really hard to dig from Facebook, so I decided to extract it and mine it via their API. To my surprise, I discovered I have a couple friends who went to the Galapagos and posted amazing photos of their trips. I realized there was a gold mine of travel artifacts buried in Facebook and thought it would be super-useful and fun to discover new places for my next vacation.”

Tabet was a founding engineer at Trulia, a real estate startup that recently went public with a $75 million initial public offering. As you can see from his personal infographic, Edouard and his friends have visited 76 countries, and one out of nine of his friends have been to Paris.

If friends hold similar preferences when it comes to pastimes, lifestyle, and interests, it makes sense that these commonalities would extend to travel destinations. Furthermore, asking a friend about their personal experience of a place is probably preferable to blasting out inquiries to your whole social network, reading travel guides, or perusing blog after blog for advice.

Travel writer Tim Cahill said, “A journey is best measured in friends, rather than miles.” In both cases, Zetrip provides the yardstick. The company is based in Mountain View, Calif., and is currently fundraising.