"But what's it for?" I said. "I don't really see the point."
It was last March (2008). I was standing in front of the Starbucks at the hotel in San Diego during the etech conference, and I had just discovered that the guy standing next to me in line was Matt Biddulph, one of the founders of Dopplr, a social network specialising in travel. Like Flickr, only with a lot less to look at.
I joined Dopplr in June, 2007, a shortly after the service was founded. Not, I hasten to add, because I'm one of the cool people or because I'm a rapacious early adopter but because someone I knew who presumably knew a cool person or an early adopter sent me an invitation with the note, "This looks like a useful service." Like I say, it's a social network, so friends invite friends, who invite more friends. At least, they say they're friends. (Friends don't let friends join social networks.)
Pretty much the only thing you do on Dopplr is post trips: where you're going and when. So do your friends. You look at each others' travel schedules. You can write notes on your trips ("There is nothing whatever to do in..."). Dopplr can email you updates. Which is how, a couple of months ago, I discovered that a friend from Seattle was visiting London. It was, actually, nice to see her again.
These are people who meet in cyberspace and at conference; where everyone lives doesn't always stick in your mind. For this group, automating updates makes sense, even if, like me, you're in the habit of posting where you're going on your blog. And then there's FOAFs - making the network about travel plans gooses the basic social networking assumption that you and your friends' friends are likely to share interests and compatibilities. Since its founding, Dopplr has added a Facebook integration feature.
But that's not a business model. This week, Dopplr had a party - which attracted 400 users and investors from 25 countries - to celebrate closing its second round of funding. The phrase "intention-based" was tossed around a lot, not least by Biddulph, who seemed to remember our Starbucks conversation charitably.
"What," Tyler Brûlé from Monocle, which hosted the event, asked, "is the only thing that would make a long flight better? Sitting next to somebody you like." Most travel sites have, he said, been more obsessed with finding the right bag.
I think one reason Dopplr seems weird and of uncertain value to some is that it began as a largely empty site. In building an online community, this is actually a good thing. One of the fastest ways to strangle a new online community at birth is to build too much structure and content; it squelches incoming members' creative desire to contribute. Conversely, build too little and people stumble around wondering what to do (a problem that plagues Second Life for many people once they get past the novelty).
Dopplr seems to have gotten that balance about right, judging by the slow but steady growth in usage to date, and beginning with friends and friends of friends (the site opened to the wider world in December 2007) meant the early adopters began with the necessary mutual trust. People can write notes about their trips, add tips for other travelers to the same location (want to know the best Japanese restaurant in Las Vegas?), or see who among their friends has spent the most time in the city they're about to visit. (Dopplr has also added a carbon calculator, so that some of the world's geekiest and most prolific travellers can feel appropriately guilty.)
The site's next steps involve "partner brands" - less crass, I suppose, than advertising: sponsors who can help with up-to-date information (Monocle) or suggest niche hotels (the Chiswick boutique hotel specialist Mr and Mrs Smith). Talking to Biddulph, a couple of other ideas readily sprung to mind, such as a network of Swiss Army knife lenders for people who don't like to check their baggage.
Biddulph's point - and I suspect he really is right about this - is that knowing where someone is going to travel is a powerfully valuable piece of information. Eventually, the site will also probably produce the kinds of statistics that are valuable, but at the moment it's still too small and its users too closed a group to produce much of value. For example, it seems that one of the most popular destinations of the year is Montelieu, in France - it's where the World Wide Web Consortium held its plenary. Or consider the extremely popular Black Rock City, which only exists once a year (kind of like Brigadoon, only more often): it's where they hold Burning Man. These are not trends that are likely to prevail in a truly mass-market site, and Biddulph knows this: "We can't do business intelligence - not until we're really big."
Can it get really big before airports are filled with protesters who lobby gold travellers the way animal rights activists campaign against fur-wearers? It's still not clear to me whether it's an application or a feature. But Dopplr now has time to find out.
Wendy M. Grossman's Web site has an extensive archive of her books, articles, and music, and an archive of all the earlier columns in this series. Readers are welcome to post here, at net.wars home, at her personal blog, or by email to email@example.com (but please turn off HTML).