Hewlett-Packard this week launched a new online promotion that discounts several consumer PCs by $150 when equipped with Windows 7, saying the four-year-old OS is "back by popular demand." "The reality is that there are a lot of people who still want Windows 7," said Bob O'Donnell, chief analyst at Technalysis Research, in a Monday interview. "This is a twist, though, and may appeal to those who said, 'I do want a new PC, but I thought I couldn't get Windows 7.'"