Ah, Google (NASDAQ:GOOG). The online-search giant reported stellar earnings last week, but its stock hardly budged. Is the magic gone?

Admittedly, there were some impressive elements to Google's second quarter. Net income more than doubled to $721 million, or $2.33 per share, and revenues rose 77% to $2.46 billion. Meanwhile, much has been made about the search leader having taken further market share from Yahoo! (NASDAQ:YHOO) -- and, of course, Microsoft's (NASDAQ:MSFT) search aspirations seem to be falling short at the moment.

So why the lackluster response? I have to wonder whether more investors are starting to fret about how long Google can keep it up. I recently outlined what I believed to be a series of risks (10, in fact) pertaining to Google, not the least of which is that just about all of its revenue comes from a single source. Foolish colleague Seth Jayson discussed the risks pertaining to click fraud and other threats to sales growth, and the issue has a high profile this week, with Google in court pushing for a $90 million settlement in a class action suit.

Furthermore, Google has already admitted that its rate of capital expenditures is due to be "substantially greater" than its sales growth this year, as it invests in servers, networking equipment, data centers, real estate, and campus facilities. Here's a red flag: Despite the fireworks, while Google generated $480 million in free cash flow last quarter, it generated only $142 million in FCF this time around. Google has its work cut out for it to maintain its strong growth, especially with major competitors obsessed with getting a piece of the pie, and it has to increase capex to do it. (And what's this about Google buying a Boeing 767?)

In browsing through news coverage over the days since Google released earnings, I ran across some articles that spelled out risks for Google but also posed the idea that its being "different" from other companies will justify its high price in the future. For me, that raised the specter of a certain "boom" -- when people insisted that new economy stocks were "different" and threw all caution to the wind.

Folks on our Google-dedicated discussion board here at The Fool have described me as being "schizophrenic" about the company. I admit, when I write about the search giant, I often get excited about the business but remain unenthusiastic about the stock. (Maybe it takes one to know one -- last week, Fool Tim Hanson posed the idea that those Google guys might be crazy, though crazy in a good way.) At any rate, it appears that while Google may still have a lot going for it, investors expect more, especially given some of the nagging doubts that are emerging.

Microsoft is a Motley Fool Inside Value selection. To find out what other companies Philip Durell has recommended for value-oriented investors, take a 30-day free trial.

Alyce Lomax does not own shares of any of the companies mentioned.