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 auto parts retailer Advance Auto Parts (NYSE:AAP) climbed as high as 10% today after its quarterly earnings easily topped Wall Street expectations.

So what: The stock has slumped over the past year as rebounding demand for new vehicles has hurt sales for used auto parts, but a wide fourth-quarter profit beat -- EPS of $0.88 versus the consensus of just $0.76 -- suggests that things are starting to pick up. In fact, close rival O'Reilly Automotive (NASDAQ:ORLY) is also surging today on better-than-expected results, giving Wall Street a particularly good feeling about the industry as a whole.

Now what: Management now sees full-year 2013 adjusted EPS of $5.45-$5.60, versus Wall Street's view of $5.57.

"Our decision to maintain our investment profile through the course of the year is driven by our confidence in the long-term industry fundamentals and provides us with a strong foundation to build upon as we head into fiscal 2013," said Vice President and CFO Mike Norona.

More important, with the stock still down about 20% from its 52-week high and trading at a forward P/E of 13, buying into that optimism won't come at too high of a price.

Interested in more info Advance Auto? Add it to your watchlist.

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.