Tech investors might have been fixated on Netflix's (Nasdaq: NFLX) 22% explosion today; the company turned the tide on streaming customer defections and posted a stellar quarter. However, aside from Netflix's gain, the Nasdaq had a pretty soft day, closing down 0.46%. Rounding out the losers was flash-memory provider SanDisk, which posted weak results in large part because high sales from Apple crushed other mobile companies SanDisk supplies. Likewise, Logitech also posted disappointing earnings as weakening PC sales in markets like Europe and the United States led to a 5% sales fall-off from last year.

The message?

Technology is rapidly evolving. While some companies are claiming to make the jump, earnings season often sorts out the contenders who will rule the next sea change in technology against the pretenders that aren't seeing traction. With that in mind, let's take a peek at four exciting technology companies that all in one way or another are at the forefront of growth fields in technology and see why they're either soaring or plunging after hours.

Popping!

  • Informatica (Nasdaq: INFA): The company posted revenue of $227 million and EPS of $0.47, beating analyst estimates of $226 million in sales and EPS of $0.44. Its full-year revenue guidance was unchanged. The fact that such a modest beat -- and lack of upped guidance -- is producing a 6% after-hours gain seems a bit generous. Free cash flow dropped from last year, and the company's growth in unearned revenue -- an important measure of new long-term contracts for IT companies -- declined from last year. If anything, Informatica is rising because it shed more than 25% in the past six months, thanks in large part to IT-spending uncertainty, and investors were expecting management would have a hard time sticking to its full-year targets.

Dropping!

  • Riverbed Technology (Nasdaq: RVBD) is sinking by a whopping 14% after hours. While the company exceeded expectations for the current quarter, its first-quarter guidance of $0.19 to $0.20 was below estimates of $0.25 per share. Riverbed came into earnings trading at a sky-high 88 times earnings, and when you're a growth company that can't meet expectations in a see-sawing market, you get hit hard. While the company appears to be hitting a minor bump in the road, it's still the dominant player in a powerful niche of technology. Throw in the fact the company is in the midst of a major product refresh to its flagship Steelhead appliance, and that Riverbed is expanding to an adjacent market with a new product, and I think investors are overreacting to a short-term blip in earnings. Long story short, Riverbed's placement at the center of a rapidly expanding market looks secure.
  • After preannouncing that it would trounce earnings, Cirrus Logic (Nasdaq: CRUS) reported earnings tonight in line with its previous boost to guidance and guided above expectations for next quarter. Then the stock promptly plunged 7% in after-hours trading.

    Huh?

    After that drop, earnings settled back in to a loss around 3%. While the drop might seem unwarranted to investors it's worth noting that Cirrus Logic is up 37% over the past month. That jump comes largely on the back of riding Apple's record quarter. Cirrus Logic now sees a stunning 70% of its revenue from Apple. While that's a huge risk, it also means that if Apple trumps earnings estimates again next quarter, it should drag Cirrus ahead with it.
  • Finally, Juniper Networks (NYSE: JNPR) stepped up to the earnings plate tonight and also whiffed. The company had already pre-warned that the quarter's earnings would come in light, but its guidance for next quarter also scared investors. The telecom sector has been reining back capital spending, which has been a drain on Juniper. Unfortunately, with AT&T and Verizon both posting uninspired earnings this week, the bottom in the market could still be a long way off.

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