Buried in the depths of its filing for a listing on the US public markets yesterday, Facebook highlighted its partnership with TripAdvisor as a prime example of how external sites are using the social graph.
While analysts and tech-heads pored over the finer details of the S1 filing with the Securities and Exchange Commission, shedding light on some of the company's financials for the first time, TripAdvisor will no doubt be overjoyed at the inclusion of the Trip Friends system it integrated in June 2010.
Facebook is looking raise around $5 billion from the IPO in the US.
The S1 revealed Facebook's profit in 2011 was a staggering $1 billion, gleaned through revenues of $3.71 billion, while founder mark Zuckerberg still owns around 30% of the business.
Facebook currently has 845 million users worldwide, with more than half using the network every single day.
What surprised some was the letter from Zuckerberg at the head of the filing, in which he pretty much warned investors that Facebook wants to stick to its so-called ethos:
"Facebook was not originally created to be a company. It was built to accomplish a social mission — to make the world more open and connected.
"We think it’s important that everyone who invests in Facebook understands what this mission means to us, how we make decisions and why we do the things we do."
He continues:
People sharing more — even if just with their close friends or families — creates a more open culture and leads to a better understanding of the lives and perspectives of others.
"We believe that this creates a greater number of stronger relationships between people, and that it helps people get exposed to a greater number of diverse perspectives."
In terms of the integration used by TripAdvisor, basically a enhanced version of Facebook Connect, Facebook says the service illustrates how third party sites can "design more deeply integrated social experiences built around users and their friends".
"By tapping into our rich social data, TripAdvisor connects users to their friends and shares relevant content about where their friends have traveled and where they would like to visit in the future.
"While on the TripAdvisor website, friends can discuss their travel plans and recommendations and build out personal profiles of places they have been."
While initially it did seem to some sceptics to be just another fancy feature that people wouldn't use, over time it appears to have started having quite a significant impact.
A TripAdvisor official says by December 2011, over 57 million people had "personalised their trip planning experience" on the site using Trip Friends.
Furthermore, these people are twice as more likely to contribute content to TripAdvisor than its other users.
No wonder Facebook likes talking up the Trip Friends integration in probably the most important documents the company has ever produced.
NB:Facebook Like image via Shutterstock.