With more than 60 million unique visitors a month, hi5 is continuing expansion of its gaming efforts. The San Francisco-based company is launching a brand new downloadable games section for its Games Channel today. Powered by RealNetworks, it will distribute more than 1,500 RealGames titles.

Since it transformed from a “social network”  into a social entertainment company earlier this year, hi5 has focused heavily on its gaming. It added the New Zealand-based virtual world SmallWorlds, Playdom’s Poker Palace and RockYou’s RockYou Pets to the platform. It also brought in Mochi Media’s collection of 7,000 Flash titles. Most of these games are monetized through the company’s universal virtual currency (hi5 Coins).

Since making the changes, hi5 has steadily grown, becoming a top 20 site worldwide.  hi5 Games alone reach nearly 5 million monthly unique visitors and receive more than 3 million daily game plays since launching back in February.

Not only does the library of downloadable games provide yet another revenue opportunity for hi5, it gives users an impressive range of downloadable games from roughly 20 game genres. This includes casual titles such as PlayFirst’s Diner Dash, core games such as Grand Theft Auto IV and Gears of War, and classic games from developers like Atari. These downloads will consist of trials and full games. They vary in price (from free to $50).

“Adding downloadable games expands our overall value proposition to gamers and presents a promising new revenue stream for our social entertainment business,” said Ramu Yalamanchi, founder and chief product officer of hi5. “This partnership allows us to address a broader range of entertainment interests for our millions of active users, from casual gamers to core gamers, with many of the top PC game titles.”

Freemium games revenues are becoming increasingly important to the future of the PC gaming industry. Based on reports from DFC Intelligence, PC online game revenue, not including retail sales, is expected to grow to approximately $19 billion by 2013.