Fresh off the heels of Apple announcing a nearly 30% increase in Mac shipments from the year-ago quarter, research firm IDC has pegged Apple's U.S. market share for the December quarter (Apple's fiscal 1Q 2007) at 4.7%, up 1.1% from 3.6% the year ago quarter.
Apple saw another quarter of very solid growth as the company combined new portable products with strong retail sales and positive press following a successful transition to Intel processors. Worldwide and U.S. shipments were each up roughly 30% year on year. The company also continues to benefit from its music business and new developments such as the iPhone will not only drive more positive press and buyer interest, but further expand the number of people using at least one Apple product who may come into the Apple fold.
While Apple's market share numbers are down from last quarter (Gartner), the fluctuation is likely a seasonal swing. Appleinsider quotes a PiperJaffray analyst who expects Apple's numbers to bounce back once professional customers begin buying when Adobe CS3 ships.
Apple remains #4 in IDC's rankings of U.S. shipments, but is not listed in the preliminary world rankings.