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 Goodyear Tire & Rubber (NYSE: GT) have been steadily motoring higher throughout the day -- currently up 10% -- after Bank of America Merrill Lynch upgraded the company to "buy" from "underperform."

So what: Bank of America Merrill Lynch analyst John Murphy cited an attractive valuation for his upgrade, following Goodyear's protracted downward move this year. Goodyear has doubled from its March 2009 lows, but remains a far cry from its all-time highs set in 1998. It's essentially been in a long-term downtrend ever since.

Now what: Let's remember that analyst upgrades and downgrades are usually short-term events that shouldn't radically change our long-term perspective on a stock. Today's upgrade provides a short-term boost to current shareholders of Goodyear, but it does little to explain how it plans to deal with its nearly $5 billion in long-term debt, or how it intends to stay consistently profitable in a still-turbulent auto market. With automakers Ford (NYSE: F) and General Motors (NYSE: GM) still on the mend, I don't think it pays to let today's bullishness sweep you off your feet. Goodyear's inconsistent earnings history over the past decade leads me to believe that it might be best to let Goodyear prove it with profits first, before you lock onto the buy button.

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