Absolutely, it does already. AgriMarine, which used to operate the land-based tank farm at Cedar before they moved away from the technology because it was just too expensive to run, were marketing a farmed salmon as “eco” salmon in local stores.
Right now there are land-based farmed salmon—I think coho—coming out of a farm site in Washington State that are a “best choice” in sort of the SeaChoice and the Monterey Bay Aquarium Seafood Watch program.
Eco-certification is here. It's not going to go away. Is it a good thing? I think it is, absolutely. If people want to choose products that are differentiated from other products that they see as problematic, I think people should have that opportunity to vote with their wallets and buy something. If it costs more and they're happy to pay more, they should be able to do that.