With pick junglers like Evelynn, Rengar, Kha'Zix, Lee sin or Elise getting forever nerfed and mid-game bruisers getting screwed over, the natural evolution is S2 late game turtling style. One of the reason that we don't see Renekton anymore, but we see Dr. Mundo and Ryze more than ever is because it takes an insane amount of skills and efforts to manage to close a game before they become big. I'm fairly confident that at world we'll have 2 main metas :
#1. Late game monsters
You'll either have the little ball of death variation with something like "Lulu - Nunu - Zilean - Tristana - Janna", which basically gives 25k in stats to your ADC and so many shields/heals that she's basically unkillable, or the CLG.EU "Dr. Mundo - Kha'Zix - Xerath - Kog'Maw - Braum", which is focused more around having 1 major threat with 1 long rage wave clearer and basically siege for millenaries.
#2. Mid game pubstomp
If you feel like you're much better than the other team, you also have the option to run a mid-game comp, with things like "Trundle - Nunu - Zed - Corki - Thresh", where your goal is simply to brute force things mid game.
What could end up being the #1 succesfu lteam could maybe be something inbtween, maybe something like "Trundle - Kha'Zix - Syndra - Corki - Braum", where your team goal is to get ahead early and keep ahead, but later on you also have syndra's poke + Kha'Zix' damage to be able to offset Corki's lesser scaling. Also, even if Kha goes mostly damage items, you'll end up with Braum+Trundle as a front line.