Hubs have been around for a bit now, and they haven't started a community revolution that I can see and I haven't found many uses for them in my own usage of the site.
Except for one.
As far as I can tell, the absolute best use of a hub is to make a private one with all your own models in it. You can then see everything people post to your models with one click. That's massively convenient and I heavily recommend it. Obviously the usefulness trails off for the people with multiple hundreds of models since a hub can only hold 50 entries, but those people likely weren't checking their models by hand either.