Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Chinese real estate Internet portal SouFun (NYSE: SFUN) aren't having so much fun today, down by as much as 13%, after the company reported fourth-quarter earnings.

So what: Revenue rose 15% to $113.9 million, with earnings per share turning out to be $0.49. The top line beat the market's expectations while the bottom line fell short by a nickel. Full-year revenue jumped 53% to $343.8 million.

Now what: What's really weighing on shareholders is the relatively soft guidance that SouFun issued. The company sees fiscal 2012 sales between $380 million and $400 million, while the Street was looking for $412.6 million on average. Add in the overall pessimism in the broader market today and you get a recipe for a mean sell-off.

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