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 robot maker iRobot ( NAS: IRBT ) plunged a staggering 32% today after its full-year outlook came in well below Wall Street expectations. So what: iRobot's fourth-quarter profit jumped 52% year over year, but a disappointing 2012 outlook is forcing analysts to seriously lower their valuation estimates. While its consumer segment continues to see strong growth, slowing sales to government agencies is triggering concerns over the company's long-term potential. Now what: For 2012, iRobot expects EPS of $0.75-$0.95 on revenue of $465 million to $485 million, well below the consensus EPS estimate of $1.44 on a top-line of $532.7 million. "As we look at 2012, we feel very good about the growth opportunity for our home robot business in 2012 and beyond," CEO Colin Angle said.