In a previous post, I mentioned we were working with a new client on a GWO test — and that this client was among the busiest websites in the world. I couldn’t reveal the identity of our client then, but I can now. According to Alexa, the world’s 3rd busiest website:


With over 1,000 combinations and millions of visitors per day, this was one of the largest GWO multivariate experiments ever implemented. If there was ever any question as to whether GWO was robust enough to handle large-scale experiments, those doubts have now been put to rest.

The goal of our first test was to increase account sign-ups from YouTube’s home page. The results exceeded our expectations: the winning combination boosted account sign-ups by 15.7%

With a site this size, there are always lots of things to test. And we’ve already moved on to our next GWO project with YouTube. But of course, the details are secret for now. Stay tuned…

Ed.: Youtube has written about this on their blog, giving more details.