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 Halliburton (HAL 0.22%) gained slightly on Wednesday after Raymond James upgraded the oilfield service gorilla from market perform, to outperform.

So what: Along with the upgrade, analyst J. Marshall Adkins planted a price target of $63 on the stock, representing about 29% worth of upside from its Tuesday close. While value investors might be turned off by the stock's hot run in 2013, Adkins expects Halliburton's North American operations to pick up significantly next year, giving investors plenty of room for even further gains.

Now what: Raymond James sees a few key factors working in Halliburton's favor. "Our continued optimism on 2014 North American E&P capex is a theme we've been consistently touting," noted Raymond James. "Our optimism is fueled by 1) upward bias to consensus EPS via North American operations, 2) upcoming Analyst day, and 3) option value in international turnaround." With Halliburton shares up about 60% from its 52-week lows, and trading at a 20-plus P/E, however, I'd wait for a wider margin of safety before buying into that optimism.