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

What: Shares of Tiffany & Co. (NYSE:TIF) climbed nearly 2% today after Canaccord Genuity upgraded the jewelry retailer from sell to hold.

So what: Along with the upgrade, analyst Laura Champine boosted her price target to $83 (from $65), representing about 7% worth of downside to Friday's close. While Champine isn't exactly thrilled over Tiffany's appreciation prospects, she believes that continued margin expansion should limit the risks in 2014. 

Now what: Canaccord raised its 2014 EPS estimate for Tiffany by $0.41 to $4.51 on a gross margin increase of 195 basis points. "We think our prior gross margin outlook for Q4 and beyond was conservative given persistent metal and diamond cost deflation and price increases that have only recently begun flowing through the P&L," noted Canaccord. "Our longer-term projections also reflect further margin opportunity through fixed cost leverage and product mix as new products aim to revive the silver business." With Tiffany up more than 60% from its 52-week lows and trading at a P/E of 25, however, I'd wait for a wider margin of safety before buying into that opportunity.