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 CenturyLink (NYSE:CTL) climbed 2% this morning after Macquarie upgraded the integrated telecommunications company from neutral to outperform.

So what: Along with the upgrade, analyst Kevin Smithen boosted his price target to $33 (from $31), representing about 14% worth of upside to yesterday's close. While momentum traders might be turned off by the stock's steady decline over the past year, Smithen believes CenturyLink is a rather timely opportunity given the mounting pressure on management to unlock value.

Now what: According to Macquarie, CenturyLink's risk/reward trade-off is pretty attractive at this point. "We point out that [Frontier Communications] has shown an interest in acquiring more rural access lines and believe divestitures could be one scenario for CTL," noted Smithen. "In our view, all of the options we looked at have the potential to return 20+% to shareholders over the next year." With the stock boasting a juicy 7.5% dividend yield, contrarians who commit will even get paid to wait for the thesis to play out.