Beyonce and rapper Nas have kicked off 2007 in style by claiming the top spots on the first US singles and album charts of the New Year. Beyonce's IRREPLACEABLE is proving to be just that by securing a fourth week at the top of the Billboard Hot 100, while Nas scores his third number one on The Billboard 200 this week with his eighth album, HIP HOP IS DEAD. The rap star's new release moved 355,000 copies in the last week of 2006 to claim the New Year number one. Another rapper, Bow Wow, also starts 2007 on a high note - his latest album, THE PRICE OF FAME, has debuted at number six on the New Year chart.