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 Micron Technology (MU 2.83%) climbed 1% today after Citigroup boosted its price target on the stock.

So what: Analyst Glen Yeung maintained his hold rating on Micron, but the new price target of $30 (from $19) represents a whopping 62% worth of upside to Friday's close. While value investors might be turned off by the stock's red-hot run over the past year, Yeung thinks that the strong likelihood of higher prices for Micron's DRAM products gives it plenty of more room to run.

Now what: Yeung doesn't expect Micron's rivals to fight for market share as intensely as they did before. "The DRAM industry has heightened potential for a sustained period of profitability, atypical of the industry's past," Yeung noted. Of course, with Micron shares up a whopping 265% over its 52-week lows and trading at a clear price-to-sales premium to the industry, it's hard to believe that those bullish expectations aren't already baked in.