Since the beginning of the presidency of Barack Obama for a certain segment of folks there has been a long held desire to see the president say something worthy of some rando dude in the crowd (preferably a hype man. Is that an official White House position?) to shout "Tellemwhyyoumadson!"
Tellemwhyyoumadson is a very East Coast, largely New York City expression. But the phrase -- which is a perfect thing for a hype man, your boy, your frat or a very devout follower of yours to shout -- is essentially an "amen corner" kind of thing. To shout "Tellemwhyyoumadson" is essentially like saying "That's right!" or "I agree with your point, please continue to elaborate on these fools."
At The Root, scholar and occasional racial polemic John McWhorter elaborated on this.