Despite the software giant's aspirations, Microsoft's older Windows XP is still the newer Windows Vista's biggest enemy. It's cheaper, a known quantity, and "good enough." The software developer has, in some measure, conceded this by allowing PCs to be preloaded with the older OS for an additional five months and, in emerging markets, until the middle of 2010. Copies of XP will also continue to be available at retail. [News.com]