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 Chipotle Mexican Grill (NYSE:CMG) climbed 2% today after Morgan Stanley upgraded the burrito purveyor from equal-weight to overweight.

So what: Along with the upgrade, analyst John Glass boosted his price target on the stock to $485 per share, representing about 16% worth of upside to Friday's close. Morgan Stanley's AlphaWise consumer survey showed that Chipotle still has best-in-class value scores, indicating strong future traffic growth, room for margin-expanding price increases, and, in turn, plenty of room for investors to profit despite the stock's red-hot price action.

Now what: Due to those positive factors, Morgan Stanley raised its EPS estimate for 2014 and 2015 even further above the consensus. "[W]e see the debate shifting on [Chipotle] as it increasingly articulates its vision of developing additional concepts (ShopHouse may just be the beginning), significantly expanding the total addressable market and supporting the multiple," wrote Glass. "While valuation is not the most compelling selling point now, historically owning best-in-class growth has rewarded LT shareholders." Of course, with the stock hitting a new 52-week high today and trading at a 30-plus forward P/E, I wouldn't take too big of a bite at these levels either. 

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool recommends Chipotle Mexican Grill. The Motley Fool owns shares of Chipotle Mexican Grill. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.