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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.