While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Nordstrom (NYSE:JWN) slipped 2% this morning after Goldman Sachs downgraded the department store operator from buy to neutral.

So what: Along with the downgrade, analyst Stephen Grambling reiterated his price target of $74 on the stock, representing about 9% worth of upside to Friday's close. So while momentum traders might be attracted to Nordstrom's recent price spike, Grambling's call could reflect a sense on Wall Street that its valuation is becoming a bit stretched.

Now what: According to Goldman, Nordstrom's risk/reward trade-off is pretty balanced at this point. "In our view, JWN remains well positioned to benefit from secular and cyclical trends within our broadlines coverage with the best bricks, most clicks and off-price growth," said Grambling. "Additionally, JWN is the most levered to an improving economic backdrop. However, recent outperformance leaves the shares trading at 16.5X NTM P/E on our above consensus EPS estimate, which is approaching the 5-year peak." Given Goldman's solid stock-picking track-record -- currently ranked in the top 10% of our CAPS community -- Fools might want to keep watching Nordstrom from the sidelines.