Even though this is Wired, this is typical of financial reporting: to take a single day of price movements and write whole stories about them, completely ignoring larger price movements or alternative explanations. I've even seen news articles about stock market movements changed after the price swung from negative to positive in the same day... but the article kept the explanation for the price movement essentially the same! My guess is that this Wired story would have found a way to be written regardless of what the stock price did. But, getting to say that it "dove 7%" makes for good headlines (even if soared 8% just the day before, meaning that it just "dove" back to its original price).

While I don't think Zynga is a great company to invest in, its stock price is very volatile, which probably makes for good frequent attention grabbing headlines. Sure, this news was part of the reason the stock price was down, but apparently market price setters still think the company is 13% more valuable than it was 30 days ago.