Plus – hear Timberlake's Michael Jackson cover as he reveals work on Pharrell Williams solo album
Singer says he is 'excited' for fans to hear songs from forthcoming album 'The 20/20 Experience 2 Of 2'
The second volume of 'The 20/20 Experience' will be released on September 30
Justin Timberlake and Macklemore lead the nominations with five nods each
The whole album clocks in at 74 minutes and 28 seconds
'Mirrors' singer takes a light-hearted dig at the former 'X Factor' band
'I respect his opinion because I think he's a genius,' says singer of rapper
Singer says boyband's performance was just a one-off
Timberlake's bandmates join him on stage during the singer's 15-minute greatest hits medley
Timberlake last performed with his ex-bandmates in 2004