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 Williams-Sonoma (WSM 1.73%) gained about 1% today after Piper Jaffray upgraded the home products retailer from neutral to overweight.

So what: Along with the upgrade, analyst Neely J.N. Tamminga raised his price target to $85 (from $71), representing about 26% worth of upside to yesterday's close. So while contrarian traders might be turned off by Williams-Sonoma's price strength in recent months, Tamminga's call could reflect a sense on Wall Street that its growth prospects still aren't fully baked into the valuation.

Now what: According to Piper, Williams-Sonoma's risk/reward trade-off is rather attractive at this point. "We are upgrading our rating on WSM shares from Neutral to Overweight in view of the company's superior tech-savvy initiatives aimed at driving DTC revenues (already $2B in revenues and 48% of total) higher while delivering best-in-class personalized customer service supported by a catalog heritage in an agile culture grounded in a tech-rich talent pool headquartered in San Francisco," said Tamminga. "This unique positioning is coupled with a favorable backdrop of a multi-year positive cycle on the 'home' category." When you couple those strong headwinds with Williams-Sonoma's rock-solid financial position, it's tough to disagree with Piper's upgrade.