FarmVille creator and upstart Zynga could be worth more than the more established Electronic Arts.

According to a valuation on SharesPost, which analyzes the value of private companies, Zynga is currently worth about $5.51 billion. As of this writing, EA's market capitalization stands at $5.2 billion.

Admittedly, valuations on SharesPost are not an exact science. The firm says that it calculates a company's value based on "recent transaction prices, current posts, research estimates, and recent last round venture financial valuations." But considering that the companies it analyzes are private, there is no way to know exactly what a given company is worth without having some inside information.

Still, the SharesPost valuation gives a rough estimate that speaks to how far Zynga has come since it was founded in January 2007. The company caters to over 360 million users each month. Its games, which include FarmVille, Mafia Wars, and FrontierVille, have a whopping 65 million daily active users. Zynga now has 1,100-plus employees, and says on its Web site that it has raised $360 million from investors including Andreessen Horowitz, Avalon Ventures, Softbank, and Digital Sky Technologies, now known as Mail.ru Group.

Aside from Facebook, to which Zynga can point for much of its growth, the company also offers FarmVille on the iPhone and the iPad.

EA, on the other hand, is going through some tough times. During its last fiscal year, which ended on March 31, the company posted a $677 million loss on more than $3.6 billion of revenue. A year prior to that, EA posted annual revenue of $4.2 billion and a $1.088 billion loss.

In an attempt to reverse its fortune and capitalize on the burgeoning casual-gaming space, EA announced last week that it had acquired Angry Birds publisher Chillingo to capture "market leadership on the Apple platform."

(Via Bloomberg)