Melua and Cassidy duet due to top chart this weekend

The Katie Melua / Eva Cassidy duet of 'What A Wonderful World' is set to be number one this weekend, which will mean former X-Factor type Leona Lewis will be finally pulled away from the number one spot. As previously reported, the duet, which features a posthumous performance from Eva, has been released in aid of the British Red Cross. Some had given it good odds to be Christmas number one, but is likely to peak early with the new X-Factor winner expected to go top on the actual Christmas chart.