TripAdvisor trots out social network

For example, calling a person four degrees removed for advice on where to stay in Uppsala or asking for a dinner invitation when visiting someone's home city of Novosibirsk, is already socially accepted behavior for travelers.

TripAdvisor has made it painless to register your network of travelers, the point at which many sites often lose people. It imports contacts from Gmail, AOL, Hotmail, MSN, Outlook and Outlook Express. Check off who you want to invite, and who you don't want to bother asking, but who you will preaccept if they invite you. Click Submit and you're done.

You can view your friends' networks and invite their friends to join. And here's where TripAdvisor can't lose when it comes to building community. Why wouldn't you just invite everyone on everyone's list? You're only sharing travel advice and chances are you'll have more in common with someone you tangentially know than a random poster.

Reviews from travelers within your network float above the general population whenever you do a site search. You can also view their reviews, photos and lists of favorites and exchange messages from one central location. You can also view their maps.

Included in the TripAdvisor update is a Google mashup that's the digital equivalent of the map and pushpins hanging in the family den to mark the places you've been. Again, TripAdvisor keeps its mainstream America user base in mind, keeping the interface simple and offering a list of the most popular destinations to check off and automatically add.

Travelers in the same network can view each others' maps for inspiration, or simply to argue over bragging rights. The map can also be imported to a Facebook page.

In addition, the site has added a place for people to post compliments or criticisms on others' recommendations with a "find travelers like me" feature for expanding your network in the works. You can also exchange private messages with people in your network.

One caveat to the update that savvy tech travelers may notice is that you must log in to TripAdvisor to view messages. There's no way to set the system to forward private messages as e-mails or text messages to your phone. This means TripAdvisor still remains more of an armchair travel tool than one to use in transit.