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 coin and movie kiosk king Coinstar (Nasdaq: CSTR) were falling fast today, losing as much as 17% in intraday trading after the company reported second-quarter results.

So what: Coinstar's quarterly results looked pretty darn good. Revenue jumped 22% from last year to $532 million, while adjusted earnings per share were up 26%. The adjusted EPS tally topped Wall Street's expectation of $1.17, but sales fell slightly short of the target. The quarter was driven by the company's continued expansion, including its move into Canada. The company also noted that the quarter included its launch of the Rubi coffee kiosks in partnership with Seattle's Best Coffee.

Now what: For the most part, the second-quarter results looked good, but it was the outlook for the rest of the year that fell short. Coinstar said it sees 2012 earnings per share coming between $4.60 and $4.90. According to Reuters, analysts had been estimating $4.97 per share for the year. I have a tough time seeing this as a disaster, but the Coinstar story is, after all, a growth story, and so investors will tend to get particularly antsy around signs that growth is slowing.

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