Currently no Grixis or Jund decks have placed consistently, though certain strategies could be implemented, if you wanted to pioneer them. Jeskai currently operates as either a Tempo/Burn, Token, or Combo deck. The most consistently placed deck is Tempo/Burn that plays to get in early damage quickly and close the game out from an opponent at 12-8 with Burn spells. Token is significantly less played and the Combo deck is generally not good. I played Jeskai at a GP this weekend, I can walk you through the decks if you want, unless this is enough for you.