That is an excellent question. The blog post from above was really a proof of concept and to investigate what is possible to deliver on an embedded platform. Turned out that you can run a full blown wallet on a small footprint device. Coming back to your question. We have chosen Ethereum for our prototype, but we won't be tying ourselves to it (even though there are some promising developments on that chain like PoC and Plasma). One of the core directions for the startup we're building (called AnyLedger, http://anyledger.io) is being agnostic for the underlying blockchain. Our second iteration of the prototype will involve new hardware setup (smaller size, smaller footprint) and support for other chains out there (Stellar, IOTA or even tech from Layer 2 like Lightning Network, Plasma) which are more suitable for IoT scenarios. Given that the landscape of blockchain ecosystem is always evolving, we don't think there will be a single winner for the IoT scenarios. Therefore, we believe that having a platform which can expose ioT device to multiple chains would be a compelling offer.

Thanks for the feedback btw and if you're more interested into this topic, please check our website (http://anyledger.io). We're giving away first batch of our prototypes to the community once they are ready.