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 iRobot (NASDAQ:IRBT) were falling apart today, down as much as 15% following disappointing guidance in its earnings report.

So what: The maker of the Roomba and other automated machines said that adjusted earnings per share came in at $0.21, beating estimates of $0.19, while it also topped revenue projections of $128.9 million as sales grew 17% to $130.4 million. Management credited growth in the Home Robot segment for the strong quarter and noted expansion in Brazil and a new partnership with Cisco Systems called Enterprise Telepresence. Still, analysts seemed to be disappointed by current quarter EPS guidance of $0.20-$0.25, below estimates at $0.27.

Now what: Wall Street often punishes companies for delivering poor guidance after beating estimates, and this is no exception. iRobot did raise the lower end of its full-year EPS range to $0.88 from $0.80, because of a one-time tax benefit, with the high end at $1.00, but that's only enough to make the analyst consensus of $0.94 the midpoint. I'd tend to ignore today's drop in the stock as this was a strong quarter, and the pullback seems to be mostly valuation-based as the P/E is still lofty at 37. Long-term investors should be satisfied with a report like this.

Fool contributor Jeremy Bowman owns shares of Nike. The Motley Fool recommends iRobot and Nike and owns shares of Nike. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.