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 e-commerce solutions specialist Digital River (Nasdaq: DRIV) plunged 19% on Friday after issuing a disappointing short-term outlook.  

So what: While its third-quarter results were largely in line with estimates, Digital River's fourth-quarter profit warning -- it now sees EPS of $0.32-$0.35 versus the consensus of $0.39 -- is forcing analysts to continue lowering their growth estimates. In fact, the shares are now down nearly 50% over the past six months alone and are currently flirting with the 52-week low.

Now what: I'd expect the shares to stay flattish in the short term. One of the big worries surrounding Digital River is its dependence on software giant Microsoft (Nasdaq: MSFT) (which accounts for nearly a third of its revenues), but with the soft economy continuing pressure on its other customers, investors don't exactly have a lot of positive catalysts to bet on. Of course, with the stock now trading at a forward P/E in the low teens, Digital River seems like a decent long-term opportunity as management steadily signs new deals.

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