Throughout this month, investors have focused largely on the possibility that the Federal Reserve would start to ease off the throttle in providing accommodative monetary policy to boost the economy. Yet even though some members of the Federal Open Market Committee have expressed their views about the desirability of getting the U.S. economy back on track without the need for Fed support, Fed chief Ben Bernanke made it very clear in his testimony to Congress this morning that he's in no hurry to start reversing its easy-money policies, although he wouldn't entirely rule out the possibility of tapering off bond purchases under its quantitative-easing policy. In response, the stock market predictably soared, with the Dow Jones Industrials (^DJI 0.47%) climbing as much as 155 points before giving back some of those gains when Bernanke hedged his earlier dovish comments. As of 10:55 a.m. EDT, the Dow is up 61 points, or 0.4%, while the S&P 500 is up 0.25% in a fairly broad-based rally.

All but a few Dow components have gained ground, with strength focused on pharmaceutical stocks. Pfizer (PFE 1.44%) has climbed nearly 3% after revealing its plans to divest itself of its 80% stake in animal-health division Zoetis (ZTS 6.20%). In a somewhat complex plan, Pfizer shareholders will have the right to exchange their shares for Zoetis shares at a 7% discount, with investors getting no more than 98.98 Zoetis shares for every 100 Pfizer shares they offer to trade. With the discount, the offer is likely to get full participation, in which case Pfizer's stake would fall below the controlling-interest line. The multistage process that Pfizer has used instead of a simple one-time spin-off has been highly successful, raising the prospects that other companies will follow suit in the future.

Among decliners, though, is Microsoft (MSFT 0.39%), which has fallen more than 1%. Investors have high hopes that its Xbox One entertainment console will draw in not only video game aficionados but also those seeking to use a host of other services, ranging from Skype video calls and Internet browsing to music streaming and television. But the highly competitive industry has attracted a range of other players, and after the relative failures of Windows 8, the onus is on Microsoft to get this relaunch right.

Finally, beyond the Dow, DryShips (DRYS) has fallen more than 6% as investors anticipate the shipping company's earnings release after today's close. Recent optimism has spurred greater interest in DryShips and its peers, but it'll take a long time for anticipated improvement in economic conditions to make their effects felt among shippers. With its ongoing financial challenges, DryShips needs to give encouraging guidance for its future if it wants to keep investors assured that the stock is a good investment.