Skill games have a storied history on the web, but their presence on Facebook has so far been fairly limited. A startup called BringIt is announcing the results of tests with RockYou today, though, with hopes of starting a skill-based gaming wave among existing social games.

For those not familiar with skill-based gaming, it’s a form of gambling that’s not subject to the same regulations as chance-based games like blackjack. In a skill game, players will compete against a computer or other human opponents for prizes based on their reaction time and ability at the game — factors that can apply to anything from arcade to sports to strategy games.

Usually, though, skill games are associated with quick-play arcade titles. BringIt has been testing out a Match 3 game in RockYou’s Zoo World for the past three months, tweaking its model and collecting stats.

So far, BringIt has found that 6.5 percent of users will discover and try the skill game in Zoo World. Of those, 55 percent come back daily to play again, leading to an average increase of 6 minutes and 30 seconds in session time, according to BringIt CEO Woody Levin.

Players use their virtual currency to make their bets, with better performance leading to a larger payout. The real point is not the payout but the “sink” that’s created for RockYou, though, into which the excess virtual currency of players drains — in other words, the house is supposed to win. So BringIt also reports additional revenue of $120 per thousand visitors (eCPM) to the skill game.

This isn’t the first time we’ve heard of skill gaming on Facebook. King.com has a Facebook app with about two million monthly active users, while GSN recently told us that it would offer built-in tournaments and skill gaming to other social game companies.

Both those two companies and BringIt all have significant experience in skill gaming and specialized algorithms and code designed to evenly match up millions of users. But Levin says that BringIt has an advantage in its modularity and the ease of snapping it onto existing titles.

Given the significant added revenue skill games can likely bring to social games, they’re a trend we’re likely to see more of in 2011. Levin says that he’s already working with another top five social gaming company, and hopes to enter other partnerships soon.

Along with showing off the results of its test, BringIt also announced a $1.5 million financing from Blumberg Capital, Ergo Media and  Seraph Group, for a total to date of $2.8 million.