I think it could offer a viable option for small groups on extended unsupported trips, or simply where wood is plentiful. It wouldn't be difficult to figure where break-even occurs compared to traditional stove+fuel options. Heck, I'd love one for car camping, just because.

Where it has vast implications is the developing world, where fuel gathering is a significant everyday task, deforestation is a grave problem, and smoke-related health problems shorten lifespans significantly. An efficient self-powered fan-driven cookstove is orders of magnitude more efficient than an open cookfire, which would address all three problems.