The benchmarks are very interesting. I wonder what React's performance would look like when using immutable data structures, such as those by Immutable.js (another FB project). It seems to me that you would again get the benefit of immutable data in the diffing algorithm; namely that the one can check if any data has changed just be checking shallow equality.

I really admire Elm for being a trailblazer for pushing techniques such as reactive programming, but it seems to be that it's unlikely to be very mainstream. This is why I'd love to see the performance benefits using more mainstream solutions with JS.