It's possible to fake it. But i think its real because the amount of time and money it would take to make a fake one.
It's real. The baby looks about 2 or 3. He's not in time all the time but does a bloody good job for a little kid. I think he's been watching too many Ricky Martin video's 
Well done to the kid. They all love to dance, and this one is better than most.
It's real. He's from Brazil, it's in his blood. I have a two year old myself and she loves to dance. So cool 
Yep, I think it's real. If fake his feet would have actually moved and he would have really done the samba. That wasn't the samba, but it was super super cute!
this is fake
a baby can't dance like that
this is bull
real
real [;
Its real, I've lots of babies do even better dances than that, and also Babies are doing everything now a days, take for example the little chinese smoker, and his girlfriend the little girl that smokes and drinks at age 3. This video its not fake, its funny and cute.
FAKE

real baby, real movements, not real-time, not real audio. It's been dubbed and portions of the video have been slowed down/sped up to match the music. The reason it doesn't cost millions for a fake of this sort is that it's all done in post and there's no 3d or synthetic stuff here. That's why some people think that it flip flops between real and fake.