Hi5 used to be a social network-turned-gaming platform, and one of the most popular some years ago, along with other has-beens like My Space.  Faring better than the once-popular Facebook predecesor, Hi5 is being acquired by San Francisco-based Tagged, pooling a total of 330 million users worldwide, as reported by WSJ. The purchase price was not disclosed, but is likely in the tens of millions.

Tagged acquired the assets of Hi5, which is rather popular outside the United States but has struggled to make money with different business models, most recently as a social gaming platform.  Tagged is acquiring intellectual property and technology assets, but is not acquiring on any of Hi5’s remaining employees.

The merger of these networks are looking to compete with other popular sites such as Twitter, Facebook, Google +, Orkut, Netlog and Badoo.

Both San Francisco companies started long before Facebook flourished into the social networking behemoth it is today.

“At hi5 my colleagues and I recognized the unanswered opportunity to connect new people online,” said Alex St. John, former president and chief technology officer of hi5 in a statement. “Tagged is the perfect home for hi5 as it continues to prove itself as a major contender in social.”

Tagged, which claims 100 million registered users, has been profitable for the last four years and has been growing radically, increasing headcount from about 50 to nearly 200 in the last year. The combination will double Tagged’s monthly active users to 20 million and surges the number of registered users from 100 million to 330 million.

Hi5, which was founded in 2003 with the help of Tseng, has also switched its focus to social games, although Tseng said that axle wasn’t successful. The deal ends Hi5′s effort to renovate itself from an international social network to an online gaming community, squaring off against Facebook, which rapidly overtook Hi5’s efforts as a virtual goods market and social gaming platform.

“The way you compete with Facebook is you become the leader in some other space,” said Tseng. “The downfall of MySpace (and others) was they kept trying to compete head on with Facebook and then pivoted too late. One strategy is for us to grow and dominate and take other social sites and pivot them.”

Hi5 was instrumental in bringing social gaming and virtual goods efforts, where they have created a platform around which third parties could plug their games. They had an early start but failed to climb the tree after Facebook started their own social gaming platform and incorporated more marketing and virtual goods tie-ins. Google has also jumped into the crowd after the acquisition of Slide, with the added advantage of the Android platform to really push into the mobile realm as well.

Tagged, founded in 2004 and aimed at a younger demographic, was not able to catch Facebook in the social networking kingdom. So it shifted its attention in 2007 on carving a niche as a site for members to discover new friends, including by playing social games the company developed through an in-house studio. Tagged some time back tried to buy one-time social networking king MySpace from News Corp., but the deal didn’t materialize.