Kim Kardashian West makes debut on Twitter, Instagram

Reality-TV star Kim Kardashian, who said in October she would be taking the last name of new husband Kanye West, has done so on her Twitter and Instagram accounts, though not on her official website. She had told E! News on the red carpet of her Las Vegas birthday party last year that she would make Kardashian her middle name, as her sister Khloé had done when she was married to NBA player Lamar Odom. Kardashian, 33 -- whose birth middle name is Noel -- and West, 36, went mountain biking in the Ballyhoura Mountains in Ireland on Tuesday, Fergal Somers, manager of the Ballyhoura Country tourist office, told ABC News.