[salem]

No, the big difference here is that Google's MVNO is dynamically switching between multiple providers.

Most MVNOs are just resellers of a single network. They may migrate users between networks as contracts expire, but dynamically balancing between multiple networks is less common. I'm sure many people have thought of this idea before (Apple included) but actually getting multiple carriers to agree to a deal is what's interesting about this.

It's also probable only recently feasible with a mass market phone that can handle all the difference frequencies (and potentially different network types) involved.