Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of medical website operator WebMD (NASDAQ:WBMD) soared 27% today after the company's preliminary quarterly results and outlook easily topped Wall Street expectations.  

So what: WebMD's preliminary second-quarter results -- EPS of $0.05 on revenue growth of more than 10% -- and upside guidance for the full year reinforce recent optimism over the company's recent restructuring initiatives. Management had to slash about 14% of its workforce in December due to declining drug ads, but a newly implemented sales strategy, coupled with rebounding biopharmaceutical spending, seems to be fueling a much better and faster turnaround than investors had expected.

Now what: Management now sees full-year income of between $3 million and $11 million on revenue of $485 million and $505 million, versus its prior view of a loss between $1.5 million and $13 million on revenue of $450 million and $470 million.

"[W]hile not impacting our increased 2013 guidance, we are experiencing significant new commitments for our private portal offerings, including the previously announced contract with Blue Cross and Blue Shield Association Federal Employee Program, which are expected to generate revenue beginning in 2014," said interim CEO David Schlanger.

With WebMD shares now up a whopping 170% from its 52-week lows, however, much of that operating momentum might already be baked into the valuation.

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. 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.