Tank junglers will receive Cinderhelm next patch, which gives an AoE burn like Sunfire Cape and a percent of their bonus health as additional health. This will help his clears through consistent damage (which is independent of his shield) and help him stack health more efficiently (for a larger, longer lasting shield).
The cooldown on Nautilus' E was reduced from 10s at all levels to 6s->4s and it's mana cost was reduced by 20 at all levels. Since Nautilus didn't build AP often anyways, he isn't really affected by the ratio nerf and it may be used far more frequently.
Basically, his damage will no longer disappear when his shield is destroyed and is far more reliable. This is definitely an overall buff.