Weigth for this hub?
Where'd you see it?
I like turtles
At Universal cycles.
Universal Cycles -- Surly Ultra New Disc Fat Bike Hub
It's surly, so expect they've filled any hollow spaces with lead.
Surly hubs aren't the lightest, but they're not heavy, just bomber and will outlast most other 'lightweight' hubs.
From the description of the changes they made, I doubt it will be that much lighter than the previous model.