Today i stumbled across an area in deepholm that didn't got hit by the nerfbat. The only downside is that you have to be on a specific quest so you are phased to this special area (atleast thats what i think what causes it).
At times there are up to 5 nodes up at once on my minimap and the respawn is pretty decent too. Kinda like that lake area with this insane tiger lily spawns in borean tundra only more... cataclysmic.
What you will be collecting are Cinderblooms, Heartblossoms and Elementium Ore.
You have to be at the quest Rescue the Stonefather... and Flint to be phased to this area which causes the high density/respawn (again this is altleast what i think what causes it since i never before had so many spawns in this area before i've quested in deepholm).
Here's a pic with the location plus what i've gathered in about 45 minutes. (its in deepholm obviously)
Have Fun!