Shares of Zillow (NASDAQ:

) traded sharply lower on Tuesday following a disappointing earnings report from the online real estate company. Shares were down nearly 20 percent despite an impressive rally in the broader markets. The S&P 500 rallied over one percent on Tuesday to break above 1430. Zillow's earnings actually came in line with expectations. Zillow reported a third quarter earnings per share figure of $0.07 on revenues of $31.9 million. Analysts were expecting an EPS of $0.07 on $31.66 million in revenue. However, the company disappointed in terms of guidance, predicting that sales for next quarter would fall between $30-31 million -- analysts were expecting $32.4 million. Zillow went public in the summer in 2011. Shares didn't perform well that first calendar year, but until Tuesday's drop, 2012 has proven to be much better for investors, especially when compared to other recent tech IPOs. Facebook (NASDAQ:

), Groupon (NASDAQ:

) and Zynga (NASDAQ:

), for example, have all had notable struggles, falling precipitously from their initial offering price. The weakness in Zillow's forecast might suggest a softening in the real estate market, or it could simply be a case of a high-flying recent tech IPO coming back to earth. The market might get some further insight on this matter later in the week, when Zillow's competitor Trulia (NYSE:

) reports earnings. Trulia itself is trading lower on Tuesday, although not nearly as much as Zillow, near $21.60, down about three percent. The trading a rebound in the homebuilding market has proved profitable in 2012. Year-to-date, shares of the SPDR Homebuilder ETF (NYSE:

) are up well over 50 percent. Meanwhile, Wells Fargo (NYSE:

), a bank known for its mortgage exposure, its up over 20 percent and Home Depot (NYSE:

) -- a retailer with obvious exposure to the construction industry -- has rallied almost 50 percent. Attempting to use Zillow as a proxy for the broader housing market may be foolish. The company is relatively young, and while its goals of bringing the real estate market online may pay off one day, the company is still very much growing and exploring new frontiers. In its earnings report, Zillow noted its recent acquisition of Mortech, a creator of mortgage software. Zillow also spoke about its increasing push into the mobile realm, declaring that over one billion homes had been viewed on a mobile device. Going forward, shares of Zillow are likely to enjoy a wild ride for quite some time. As it remains a young company, investors should be prepared for swings like the one seen on Tuesday.