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 Aaron's (NYSE: AAN) fell more than 13% in early trading before closing down roughly 7%. Investors soured on the specialty renter's revised guidance.

So what: Aaron's now expects to end 2011 having booked $1.73 to $1.77 a share in adjusted profits, below the average estimate of $1.78 and earlier guidance $1.73 to $1.81 in per-share earnings, The Associated Press reported.

Now what: Q3 earnings didn't impress either, unfortunately. Aaron's booked $0.36 a share in profit during the quarter, two pennies short of what analysts were expecting. Does the miss matter? Would you buy shares of Aaron's at current prices? Please weigh in using the comments box below.

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Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team. He didn't own shares in any of the companies mentioned at the time of publication. Check out Tim's portfolio holdings and Foolish writings, or connect with him on Google+ or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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