Three top Columbia House executives were scheduled to leave the company at the end of December, according to a spokesperson. They include Sharon Kuroki, executive vice president of music marketing; Mark Osterer, executive vice president and chief financial officer; and John Hofler, vice president of operations research. Brian Wood, executive vice president for video, will expand his responsibilities to include the firm’s music line. This will enable Columbia House to “facilitate decision-making and centralize operations,” the spokesperson said.