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 analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of HomeAway (UNKNOWN:AWAY.DL) slumped about 2% today after J.P. Morgan downgraded the online vacation rental marketplace from overweight to neutral.

So what: Along with the downgrade, analyst Doug Anmuth lowered his price target to $38 (from $49), representing about 22% worth of upside to yesterday's close. So while contrarian traders might be attracted to HomeAway's sharp pullback in recent months, Anmuth's call could reflect a sense on Wall Street that the company's current marketing costs are just too high to trigger a near-term rebound.

Now what: According to J.P. Morgan, HomeAway's risk/reward trade-off is pretty balanced at this point. "We believe increasing marketing spend is appropriate to grow the PPB business and we are also encouraged by healthy renewal rates and strong subscription pricing growth," said Anmuth, "but we believe visibility will be limited in the near-term and return on marketing spend could take some time." With HomeAway shares now off about 40% from their 52-week high, however, those short-term concerns might provide patient Fools with a juicy long-term growth opportunity. 

Brian Pacampara has no position in any stocks mentioned. The Motley Fool recommends HomeAway. 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.