riot wants to broaden the range of viable junglers, but they are making the initial jungle camps stronger & with more health? if anything, shouldn't this narrow the amount of viable junglers?

Currently the jungle heavily favors champs with AOE clears. The new jungle is shifting this to make junglers that are more single-target more viable. In other words, Warwick, Nunu, Fiddlesticks will be made more viable while the current junglers of Maokai, Skarner, Shyvana, Mundo will still be viable but not as dominant as they are now. So in effect, we will see more junglers

Also, Hunter's Machete. Enough said :]

hi

Just being able to clear the jungle isn't what makes a jungle viable. Current jungle meta is very gank centered. If the champ cant clear semi fast and put pressure on the map its not a good pick. Which narrows it down by allot. It's one of the many reasons you see speed types like shy and mundo get exhaust. they adapted by putting pressure on the enemy jungle as well as lanes due to their ok at best ganks.

Less pressure on lanes allows the jungle to do more thus gives way to other styles like
1.) Counter jungle- its not just buffs anymore
2.) Control- more time stopping their jungle
3.) farm

** note: you see these still but its never the main objective unless its good jungle Vs a so so jungle you can bully**

My understanding is by shifting the difficulty it will make ganking happen/expect to happen notably later in the game, which will allow junglers to farm more and junglers with a longer build up to be more viable.

There should also be extra gold in the jungle now, which will give more item dependent champions more viability in the jungle.

These two changes, along with balancing back towards single target junglers, should be enough to make people rethink what is a viable jungler (i.e. Sej jungle is meant to have a nice buff, Malz jungle apparently works fairly well as well).