(MoneyWatch) The transition to each new version of Windows has always drawn criticism. Back in 2001, even the now-beloved Windows XP was met with widespread derision for its supposedly IQ-lowering candy-colored palette. But Windows 8, the operating system unveiled last month, is getting hit especially hard.Last week, Internet guru Jakob Nielsen posted a scathing assessment of Windows 8. Based on a study group of 12 Windows users, Nielsen deemed Windows 8, in a word, "disappointing." Some of his key concerns:The dual interface. For Windows 8 users, having to contend with the traditional desktop and the platform's completely overhauled "tile" interface