DNA logic gates, Merkle's rod logic gates

So, from various sources, today I learned about a team of molecular biologists at Stanford University who’ve constructed logic gates out of the DNA transcription machinery. There is a video summary with some animations as well. While reading about all these things, I was reminded very strongly of Ralph Merkle’s nanomechanical rod logic gates, which I read about many years ago in Engines of Creation. If they can make this work cheaply, easily and reliably, there may be something to this mechanosynthesis idea of Feynman’s after all, eh?