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 Ctrip.com International (NASDAQ:CTRP) closed yesterday up 8% after Deutsche Bank upgraded the stock to "buy" from "hold."

So what: Along with the upgrade, analyst Vivian Hao boosted her price target on the stock to $65 per share (from $35.20), representing about 17% worth of upside to where it sits now. Hao cited strong booking volumes -- particularly hotel sales made via mobile devices -- for the upbeat view, suggesting that the company can continue to keep its breakneck growth rate up.

Now what: Don't expect the operating momentum to slow anytime soon. "We believe CTRP is rapidly emerging as a clear travel solution leader in mobile, aided by founder James Liang's return," wrote Hao in a note to clients. "As such, despite intensifying competition, we expect Ctrip revenue/earnings growth to reaccelerate instead of decelerating as the market expects." Of course, with the stock now up a whopping 225% over the past year and trading at a forward P/E of 45, Ctrip doesn't exactly have a wide margin of safety built into it, either. 

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool recommends Ctrip.com International. 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.