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

What: Shares of SolarCity Corp. (SCTY.DL) climbed 4% this morning after Raymond James upgraded the solar energy systems company from market perform to outperform.

So what: Along with the upgrade, analyst Pavel Molchanov planted a price target of $75 on the stock, representing about 23% worth of upside to yesterday's close. So while momentum traders might be turned off by SolarCity's sharp pullback in recent weeks, Molchanov's call could reflect a growing sense on Wall Street that its prospects are becoming too cheap to pass up.

Now what: According to Raymond James, SolarCity's risk/reward trade-off is rather attractive at this point. "SolarCity is executing well, notwithstanding the recent SG&A cost escalation showing the side effects of breakneck growth," said Molchanov. "SolarCity's position as the top non-utility downstream pure-play in the U.S. market is secure, and further market share gains (not assumed in our model) would be an 'icing on the cake' scenario." When you couple that upbeat fundamental outlook with SolarCity's ice-cold stock price, it's tough to disagree with Raymond James' upgrade.