A$AP Rocky. Although, he hasn't been impressing me lately.
A very close second is Chief Keef. I don't care what you say, Chief Keef is talented. Something about a heavy Young Chop-produced beat with Keef's auto-tuned jumble of lyrics flowing over it is great to me. I'm going to steal a line from Complex magazine that was originally reviewing Future. "A strong reliance on Auto-Tune means that sometimes his voice sounds harsh, and other times, paranoid" To me, this says it all. When I listen to Keef, lyrics are meaningless. It's all about the raw emotion he's conveying throughout every song. It's a beautiful thing honestly.