SharesPost has valued Farmville developer Zynga Game Network at $5.51 billion, according to Business Week. That means it is now estimated to be bigger than console publisher Electronic Arts, which stands at a market cap of $5.16 billion. It still has a long way to go to beat Activision Blizzard, which has a market cap of $13.9 billion.

While making such direct comparisons isn't completely accurate, nor fair, it gives us a snapshot at how quickly social network gaming is growing. Zynga was founded four years ago and already six of the 10 most popular apps on Facebook belong to it, and it has more than 210 million monthly active users.

The valuation for Zynga is so high because it is based on the growth of the virtual goods space, which by itself is at a whopping $1.6 billion this year. The social firm isn't the only one in the virtual goods game though: EA also has a toehold in that market, having acquired Playfish late last year.