It is amazing the speed of Blocks development. I love blocks and it's potential. I just hope they don't collide with themes and template design. It would be a disaster to watch one "brother" smash the other. They should evolve seamless. And I hope template design isn't getting like a 2nd choice because it is the essence of any system. Right now, the environment around blocks feels like a playground. It can led to initial enthusiasm at the beginning but also to frustration and to choosing other solutions after a while. A system has to be solid and stable to keep it's users. We cannot forget the true power of WP as a tool: it's Database control and easy feed. The connection between it's input (blocks) must be flawless. WP forever.