I think Urbit has huge potential and is a very important project on par with Bitcoin in a way. I am somewhat disappointed in the lack of existing support for bitcoin on the Urbit Network. This will be resolved over time.

I think it's important to understand that Urbit is a computing project rather than a "Crypto" project. Even though it does currently use Ethereum for Dns records. It's possible however that this dns system could be ported to another system if needed.

The long term goal of Urbit is to make networked applications that don't need a software company and teams of people to keep that software alive.

Once "Kelvin zero" is reached then software built on Urbit "in theory" should function forever.