The success of the iPod poses a “happy problem” for Apple that the computer maker hasn’t had in years: how to remain the market favorite, not just the favorite underdog, reports Reuters. Apple has sold more than 3 million of its sleek iPods, taking nearly 50 percent of the market for digital music players, and its iTunes online music store claims 70 percent of all songs bought online, the article adds. However, the company faces a renewed push by Microsoft to shape the digital standard for music on the Internet, raising the risk that Apple could again fail to hold early gains in a fast-growing market, analysts said. “The ultimate risk is that they do get marginalized, just like they did in the PC area,” Phil Leigh, an analyst with market research firm Inside Digital Media, said.