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 digital marketing company ValueClick (UNKNOWN:CNVR.DL) plummeted 17% today after its quarterly results and outlook missed Wall Street expectations.

So what: The stock has slumped in recent months on concerns over slowing growth, and today's Q2 results -- income fell 41% on a revenue bump of just 4% -- coupled with downbeat guidance only reinforce those worries. In fact, management cited continued softness in the display business and the ongoing realignment of its portfolio as reasons for the weak results, giving short-term oriented investors very little reason to stick around.   

Now what: Management now sees third-quarter adjusted EPS of $0.39-$40 on revenue of $164 million-$168 million, well below Wall Street's view of $0.43 and $180 million, respectively. "[O]ur significant affiliate marketing client wins during Q2 represent a great addition to our roster of direct, strategic relationships with major advertisers and provide us with an even stronger base for sustainable, profitable growth in the years to come," CEO John Giuliani reassured investors. More important, with the stock now off about 35% from its 52-week highs and trading at a forward P/E of 10, those long-term turnaround prospects might be available on the cheap.