So, if I understand correctly... it is an internet (such being a network of computers, with the purpose being the exchange of information), that is not the internet, in the way we know it.
Now, while I don't buy into this whole "bitcoin" deal, this network is built on what is actually, in my opinion, a very strong concept.
The naming system of "the internet", as we know it, being under the jurisdiction of governments of sorts, allows governments to have control of it. Meaning that as much free speech as we may seemingly be provided, we more or less remain in the clutches of certain governmental authorities.
.bit, however, appears to be an independent network. A private one, not dependent on the naming system that is facilitated by the hyper text transfer protocol (http).
Very similar to an in-office network in an enterprise setting, which allows for fully confidential email messages to be sent between employees, but not outside of the physical office.
The bit network, would appear to function in the same way, in the sense that it's a private network, to the effect of an intranet. But it is meant to behave as if it was an internet.
I'm only speaking off of the top of my head now, but entry to the DNS system for .bit requires admission of some sort. Kind of like a speakeasy.