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 Huntsman (NYSE:HUN) gained 1% today after Goldman Sachs upgraded the chemical products company from buy to conviction buy.

So what: Along with the upgrade, analyst Robert Koort planted a price target of $32 on the stock, representing about 19% worth of upside to yesterday's close. So while contrarian traders might be turned off by Huntsman's price strength over the past year, Koort's call could reflect a sense on Wall Street that the company's growth prospects still aren't fully baked into the valuation.

Now what: According to Goldman, Huntsman's risk/reward trade-off remains particularly attractive at this point. "We add Buy-rated HUN to the Americas Conviction List as we expect further expansion of HUN's multiple to be supported by its 1) structurally improved margin profile as a result of restructuring initiatives, 2) better earnings quality with a mix shift toward specialty businesses; and 3) better leverage to a global cyclical recovery with growth and reinvestment in a broad and diverse portfolio of chemical assets," said Koort. With Huntsman shares hitting a new 52-week high today and trading at a 30-plus P/E, however, I'd hold out for a wider margin of safety before betting on those expectations.