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What: Shares of Chinese online gaming operator Changyou.com (Nasdaq: CYOU) are floating as high as 12.5% above last night's closing price, while more than three times the average daily volume of shares are trading hands.

So what: The separately traded online-gaming unit of Sohu.com (Nasdaq: SOHU) beat analyst expectations in its fourth-quarter report and also announced that a long-awaited game will launch in March with a heavy marketing push. The company now has 2.7 million paying, active subscriptions out of a staggering 111.4 million total user accounts.

Now what: I understand that Asian countries are big gamers, and Changyou is taking advantage of that. As impressive as Changyou's customer list is, that's still just 8.3% penetration of the Chinese population, and there's a lot of work left to be done to convert free accounts into paying customers. The growth opportunity ahead of this company remains immense, yet the stock trades at just 11.6 times trailing earnings today.

Interested in more info on Changyou.com? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. Sohu.com is a Motley Fool Rule Breakers selection. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool is investors writing for investors.