Social media such as Facebook and Twitter or blogging sites have become powerful tools that influence what people buy, online researcher Nielsen said Wednesday, urging business to embrace the trend. Nearly three in four people worldwide who use the Internet have visited a social networking or blog, spending an average of almost six hours a month on them, The Nielsen Company said in a report. Of the seven biggest brands online globally, three are social media networking sites – Facebook, Wikipedia and YouTube – it said in its latest report on social media trends in the Asia Pacific region. According to Nielsen’s findings, online product reviews are the third most trusted source of information when consumers decide whether to purchase a product, coming after recommendations from friends and family. From China and India to Australia, online reviews are a major influence in buying electronics items, cosmetics, cars and food, among other things, it said.