New Year, Old Problem: Most U.S. workers would gladly change jobs if the right opportunity presented itself, according to a survey of 5,300 adults by Yahoo HotJobs. Nearly two-thirds are open to switching jobs, with an improving job market cited as the chief cause for such optimism. If true, the figure suggests concern about worker retention could intensify as companies strive to keep turnover costs low in 2007. About 39 percent of those polled cite unhappiness with wages as the chief issue, with three-quarters of that group saying their 2006 raises or bonuses were below expectations. However, only 9 percent identified salary as a key indicator of success, with 46 defining success as the attainment of a proper balance between their jobs and personal lives. Also, more than 75 percent of employees are looking for new jobs, according to a survey conducted jointly by the Society for Human Resource Management and The Wall Street Journal’s CareerJournal.com. Apparently, job seekers will have choices in the coming year. Still another survey, this one by CareerBuilder.com, found that 40 percent of hiring managers plan to add jobs.