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 men's tailored and casual clothing retailer Jos. A. Bank Clothiers (NASDAQ: JOSB) plummeted 18% today after its 2012 profit outlook disappointed Wall Street.

So what: The stock has slumped over the past few months on worries over slumping demand, and today's downbeat guidance only reinforces those concerns. While management blamed the bleak outlook largely on unseasonably warm weather, increased marketing costs and lower gross margins suggest that its promotion-centric business model just isn't as profitable as it used to be.

Now what: Management expects 2012 net income to fall roughly 20% from 2011, implying a profit of about $78 million. "Despite the disappointing earnings results on a year-over-year basis, the fourth quarter and full year of fiscal 2012 will still be very profitable," CEO R. Neal Black reassured investors. "We continue to remain very positive about the company's long-term prospects." With the stock hitting a new 52-week low today and trading at a forward P/E of 9, buying into that turnaround talk might not be a bad idea.

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