Over the past few days, DJBooth has had its ear to the wall regarding GLC and his brand new I Ain’t Even On Yet mixtape. Ready to make just as big of a splash, however, is his newly-signed labelmate, Big Sean, whose ’09 debut will be distributed by Island Def Jam. The DJ Khaled ad-lib that kicks off Billionaire may have many listeners reaching for the stop button before the song even starts, but those who persevere will be rewarded. If Sean’s raps weren’t eccentric enough, producer WrighTrax contributes an eclectic beat, complete with cash register ‘ka-ching’s. Looking for more from Big Sean? We suggest U [GET TO] KNOW BIG SEAN when his brand new mixtape drops in November.