TripAdvisor launched its flight metasearch engine almost a year ago to the day in the US, triggering much chattering in the industry as to whether it could successfully integrate it into its existing product.
A UK version was finally launched in October 2009 in what was a frenetic period for US-based engines with Travelzoo's Fly.com also unveiling its version for the Brits almost simultaneously.
Officials refuse to give away any hard data concerning the product, only to say they are "very happy" with progress so far and add that 2010 will be "strong" overall for TripAdvisor Flights.
"Millions of travelers in the U.S use our award winning meta search product, and our monthly search volumes continue to increase."
One area that might surprise many is that the international rollout of the flight engine has been limited so far to the US and the UK.
Although some argue launching international versions of complex products such as metasearch engines is notoriously difficult, officials at the UK's Skyscanner have quietly been launching international versions at a rapid rate in recent years.
Once again, TripAdvisor is tight-lipped about where it might unleash flight meta next across its portfolio of country sites, saying that for the time being its "classic" version - directing visitors to partner sites for results - remains in places such as France and Germany.
When the product was originally unveiled, officials admitted they had been working on it for around a year and said it was probably the most significant launch since the review service appeared in the early 2000s.
A string of features have been added since February 2009, officials say, including AirWatch alerts and a Fees Estimator tool.
The product's success, however, will be measured in the long-term by how much it has impacted on those elsewhere in the marketplace.
Many believed having the user review system to piggyback on would give TripAdvisor a strong advantage over the likes of Kayak in international markets (a similar situation to Fly.com and its ability to buddy up with Travelzoo).