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 Stratasys (NASDAQ:SSYS) climbed 6% today after JPMorgan upgraded the 3-D printing technologist from neutral to overweight.

So what: Along with the upgrade, analyst Paul Coster reiterated his price target of $101.50, representing about 9% worth of upside to yesterday's close. The stock has slumped recently on management's public offering of nearly 5.2 million shares, but Coster thinks that it provides investors with a juicy entry point given Stratasys' strong position in the rapidly growing 3-D printing space.

Now what: JPMorgan said that Gartner's recent forecast of 3-D printer growth (95% CAGR over the next five years) suggests strong upside to its own outlook (20%-25% CAGR), and that Stratasys is in a particularly good spot to benefit. "Stratasys has achieved a sustainable competitive position in the early adoption phase of a massive, diversified market for 3D printing solutions and is a pure-play for investors seeking exposure to the manufacturing renaissance theme," noted the firm. Of course, with the stock up about 70% from its 52-week lows and trading at a forward P/E of 40, I'd wait for some of the enthusiasm to fade again before jumping in.