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 WMS Industries (NYSE: WMS) plummeted more than 15% on Tuesday after the gaming equipment manufacturer warned of disappointing third-quarter results.

So what: Thanks in large part to falling demand for slot machines, WMS said it now expects to earn a third-quarter profit of $0.40-$0.42 per share on revenue of $191 million-$193 million, versus the average analyst estimate of a $0.51 per share profit on top line of $213.5 million. With the shares hitting a new 52-week low on the warning, it's obvious that investors aren't holding out hope for a quick turnaround.  

Now what: I'd have to agree with Mr. Market on this one. Just last week, rival Bally Technologies (NYSE: BYI) also cut its current-quarter and full-year forecast, further suggesting that it might be a while before still-struggling casinos start to invest more heavily in new equipment. In fact, even WMS CEO Brian Gamache noted that, "based on recent customer capital budgets and unit demand trends, we don't expect meaningful improvements in the industry environment over the remainder of calendar 2011 or, at this point, for calendar 2012."

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