Chris O’Brien has been promoted from staff writer to business columnist at the Mercury News, replacing Vindu Goel who left for the New York Times, according to the blog Talking Biz News. “While the column will cast a wide net over the businesses and culture that make Silicon Valley unique, Chris wants to focus his column on the new ideas, people and policies that continue to reshape this region,” business editor Stephen Trousdale wrote in an e-mail to his staff.