VentureBeat

Facebook is now the most popular social network world-wide.

The Palo Alto, Calif. company pushed ahead of MySpace in terms of number of monthly unique visitors last month, according to numbers released by web measurement service comScore today. Facebook had 123.8 million visitors worldwide while MySpace had 114.5 million.

There’s anecdotal evidence all over the world that Facebook is emerging as either a leader or chief rival in just about every market, going up against either domestically-based social networks, or more established competitors.

In the U.S., its going up against MySpace. In Latin America, it’s going up against hi5. In Asia — at least in Singapore, to one commenter — it’s going up against Friendster. And in Europe, its going up against a variety of domestic rivals.

In all cases, it seems to be growing. The reason may be that it’s just a new trend, or it may be deeper, in that Facebook users tend to share more real information about themselves.

This is the second month in a row that Facebook appears to have had the most visitors of any social network in the world, although from my understanding comScore isn’t counting another 5 million users that MySpace has under the Chinese MySpace.cn domain. If that is true (and I’m checking to confirm), then this is the first month that comScore has actually counted Facebook as the number one site.

Of course, Facebook and its rivals are all struggling to make the billions in revenue that they and many others have hoped for. If nothing else, though, the sheer reach of these sites is pretty amazing.