Seems real to me !!!
OK I'm not going to read all the replies here, but why does this of all threads have so many replies? 
Well, my fiance used to teach gymnastics to babies younger than that, and also taught karate to young kids and said there was this three year old who was AMAZING in karate, could do exactly what you told him, and very well, and was much better than his nine year old brother!
FAKE !!!!
of course it's fake!! 
FAKE
Fake but adorable
real
i believe this is real. this kid can dance better than most professionals. since he's from brazil, they are known for some really good dancers so this is real. when this kid, grows up, the kids gonna be popular just because they can dance. get it kid 
Just a note from a Brazilophile here. The kid is dancing to the song Ku Duro (roughly translated as "Hard arsehole") by Fantasmão which is actually a style of music know as pagode (different from traditional pagode). In Salvador Bahia (where it appears the video was filmed) the music is associated with gangsters, trashy areas, and low class people. Male patrons of a pagode concert typically smoke crack cocaine and prepare to fight each other while females shake their asses, hump the air, and girate their hips much like the child in the video. Perhaps you could change the name, because Samba is very different. Either way, thanks for posting! Great video!

Real! Babies can be very limber as well as observant. Put the two together and this is what you get.