According to Bloomberg, the stock value of social games producer Zynga has surpassed that of Electronic Arts, the second largest video game publisher in the world (behind Activision Blizzard.) The Farmville creators are now valued at $5.51 billion, compared to EA’s $5.22. Both are less than half of Activision Blizzards $13.9 billion, which is itself small compared to Tencent Holdings of China’s $43 billion… …