It looks like it might really take off and I can see a mass exodus of poftfolios if you don't because a lot of domain resellers will want to be at a registrar that offers it.
They're not registered at register.com, their across the network.
If dynadot joined the network and you had a domain "dogtreats" registered here and loaded into the DNN, it would be listed there at register.com and might sell via the system, getting you a sale, and a commission to both register.com AND dynadot.com
Creating their own system won't be anything like joining Fabulous's DDN network.
The beauty of joining Fabulous's system is that our domains registered at Dynadot can be displayed for sale throughout the network whenever somebody searches for a similar domain at say, GoDaddy, Enom, Tucows or Netsol. That is ALOT of reach!
Supposedly registrar partners are going to be announced at Taffic next week, but GoDaddy is in already.