Turrets actually ARE too weak (defensively) right now.
I'm sorry I doubted it, but I saw it for myself.
I was jungling and my top lane friend was Shen vs. a Cho'gath
Shen was doing excellently and by the end of the game, only died once and had a few kills and a load of assists. The Cho was not stomping him and their jungler had not even been up there yet.
But at ~15 minutes I had looked top to think about ganking or picking up a Rift, and I noticed that both turrets were gone.
CHO'GATH MELEE VS. A SHEN WITH TAUNT AND TELEPORT NOT FED BUILDS NO AD TOOK TWO TURRETS IN 15 MINUTES
Another game I was playing Devour Yi, our Diana picked up a kill on her mid laner and was going back, I nearly managed to take mid lane 1st turret by myself and this was at ~10 minutes maybe even sooner.