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

Despite a better-than-expected GDP report, the Dow Jones Industrial Average (^DJI 0.56%) is down 45 points as of 11:35 a.m. EST. Microsoft (MSFT -1.27%) was one of the index's biggest losers, while other technology companies, including Qualcomm (QCOM -2.36%), led the market lower. The sell-off in tech is somewhat ironic, given that it comes on the day of Twitter's (TWTR) IPO.

The market's move lower stands in contrast to most of Thursday's economic news. Earlier in the morning, the European Central Bank announced an interest rate cut, a move economists had not anticipated. Likewise, U.S. third-quarter GDP came in better than expected, with a 2.8% print beating the 2% expectation. Some investors may have seen that report as a sign that the Federal Reserve would curtail asset purchases, but the sell-off in stocks has intensified throughout the morning.

Microsoft gives back some gains
In recent sessions, Microsoft had been leading the Dow Jones higher, but the Windows-maker snapped back on Thursday, falling moderately. There was no particular news to account for the move, suggesting that some traders may have simply been taking profits. Microsoft shares are still up 6% over the past five days.

On Wednesday, analysts at Nomura raised their price target on Microsoft to $45. Nomura saw potential for Microsoft to boost its earnings by buying back stock, cutting spending, and spinning off noncore assets. Microsoft is also expected to name a new CEO in the near future, perhaps next month, as the company has reportedly narrowed its short-list down to just five names. No matter who gets the job, Microsoft's announcement should help clear up the cloud of uncertainty currently hanging over the company's future.

Qualcomm gives disappointing guidance
In contrast, there was obvious news to account for Qualcomm's sell-off: Although its revenue came in a bit better than expected, the company gave a disappointing forecast for future sales.

Qualcomm reported adjusted earnings per share of $1.05 on revenue of $6.48 billion; analysts had expected earnings of about $1.08 on revenue of $6.34 billion. For the year, Qualcomm's revenue was up 30% as the company benefited from increased demand for its mobile chips.

Next quarter, analysts had been expecting Qualcomm to report earnings of $1.29 per share on revenue of $6.99 billion. Qualcomm's management, however, sees the company earning only $1.10-1.20 per share on revenue of $26 billion-$27.5 billion.

Twitter surges in market debut
Social network Twitter priced its IPO at $26 per share but has surged in its trading debut, up more than 73% to about $45 per share. While Thursday's trading is far from over, Twitter's performance stands in stark contrast to Facebook, which disappointed in its trading debut, barely staying above its IPO pricing.

Based on where shares are currently trading, Twitter is worth about $25 billion, which could be a lofty valuation, given that Twitter is currently generating losses. Indeed, that valuation implies that each of Twitter's 250 million users is worth about $100; investors at these levels must be banking on great future growth.