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 ManpowerGroup (NYSE:MAN) closed up 2.4% yesterday after Bank of America upgraded the recruitment services specialist to buy from neutral.

So what: Along with the upgrade, analyst Sara Gubins raised her price target on the stock to $85 per share (from $71), representing about 14% worth of upside to where the stock sits now. A recent staffing trip to Paris confirmed that the environment in France -- where Manpower derives about quarter of its revenue -- was indeed stabilizing, suggesting the possibility of upside profit surprises in the near term.

Now what: Gubins remains cautiously optimistic over a full recovery in France. "Our MAN-weighted GDP model would suggest 8% revenue growth in 2014. We, and consensus, are more cautious at 4%," noted Gubins. "We continue to forecast a 1% revenue decline in France in 2014. Each 100bp faster revenue growth for MAN would add $0.15 to EPS, or 3%, based on a 10% incremental margin." With Manpower's shares now up about 115% from its 52-week lows and trading at a near-30 P/E, I'd wait for those headwinds to be factored more fully into the valuation before jumping in. 

Fool contributor Brian Pacampara owns shares of Bank of America. The Motley Fool recommends Bank of America. The Motley Fool owns shares of Bank of America. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.