While it's true that there's an unlikely but nice scenario in which it becomes ultra-cheap to make biological processors, I take some issue with the idea of the

While it's true that there's an unlikely but nice scenario in which it becomes ultra-cheap to make biological processors, I take some issue with the idea of them being "highly parallel." What stops us from using more highly parallel chips right now is not the expense of silicon, it's that it turns out that highly parallel chips just aren't as useful as fast chips. Nothing about the ultra-cheap biological computers scenario would change that. That would be a world of omnipresent computing, not one of parallel computing.