Dec 27, 2010 14:11 GMT  ·  By

Facebook has kept on growing even as it quickly added millions of more users. Officially, it has over 500 million monthly active users but, unofficially, the figure may be well beyond 600 million. In fact, according to the latest comScore numbers, Facebook is now the third largest website in the world, surpassing Yahoo sites in November.

What's more, data from Hitwise shows that Facebook was the biggest website in the UK on Christmas Day, something that tends to happen annually now, since regular search traffic sees a slump during the holidays.

While Facebook has been huge in the US for quite a while, it is now the third biggest website worldwide. In November, Google led the pack with 970 million unique visitors.

Microsoft wasn't that far behind, its online properties getting 869 million visitors last month. But beyond that, things changed as Facebook overtook Yahoo's websites.

Facebook had 648 million unique visitors, according to the data, while Yahoo had only 630 million. Since Facebook has always been on the rise while Yahoo has been stagnant at best, you can expect the gap to widen.

What's more, it seems like only a matter of time until Facebook becomes the biggest website on the planet, barring some completely unexpected turn of events.

Granted, it may be a while to get there, while Facebook is still growing, it has been slowing down somewhat this year. Adding more than 300 million unique visitors is not an easy task even for the mammoth social networking site.

That said, December promises to be an even bigger month for Facebook. The social networking site traditionally sees more traffic this month, especially during the holidays.

While people are less likely to go online to search for something on Christmas Day, for example, they will do so to get in touch with their friends and family.

Hitwise reports that Facebook was the most visited site in the UK on Christmas Day, with 10.77 percent of people online using the social network. The same thing happened last year in the US and there is no reason to think that it hasn't happened this year as well.