Nope, its no joke and not lip syncing. It's definatley his real voice. God! I can't believe, he's so gifted. The timing, taking breaths and he has such a huge range from high to low voices.
One of his examples, the Disney Aladdin song 'A Whole New World'. The video I've posted has reached over 10,000,000 views (phwoorrrrrr!)
I just though I'd share it with you all, you MUST WATCH THIS!