Don't listen to what anyone is saying about the jungle.

As a PBE tester, and someone who has played A LOT of jungle over the PBE over the last week and a half, jungle diversity is going to be HUGE. So many champions can clear well now (Nautilus clearing with krug buff is INSANE, I used ONE of THREE potions and was at full hp)

Firstly, the mastery Runic Armor. 8% TO ALL HEALS AND SHIELDS (THIS INCLUDES BASE HEALTH REGEN). Most junglers have some kind of heal or shield, so they benefit a huge amount from this mastery at 11 points in the new defensive tree. Rengar's clears have improved by a huge amount, allowing him to have an easier time impacting the game early if that's what he wants. This mastery will help with clearing the jungle by a huge amount and people aren't taking it into consideration. I can't list the junglers who get buffs from this mastery alone on their first clear.

Second of all, the jungle is easier and has more sustain options. You can start off with a refillable potion and turn it into Hunter's Potion, which will give you HEALTH AND MANA, has 5 charges, and will get additional charges every time you clear a camp. Is the item at full charges? No problem, it'll use the one you just earned automatically, helping you top off. If you're a jungler that still has a rather pathetic clear, you can take three potions instead (up from two now) and you sustain so much better.

Both of these combined allows you to be able to have more impact early. Lee Sin, Rek'Sai and Vi will NOT be the only available jungler options. At the very least, the only one of these champions who may be able to tank the rift herald is Rek'Sai. Bringing along a tankier jungler will allow easier taking of the Rift Herald

The only bad thing about the new item is that Hunter's Talisman is undertuned on many junglers, and will need a flat out buff at some point.

Hell, don't take my word for it if you don't want to. The pre-season is in three days.