I'm curious how the performance and scalability compares with Theano and Torch. I'm thinking the reason Google built this is that they wanted to scale computations to really large clusters (thousands, tens of thousands of machines) and the other options didn't really cut it.
This looks to be a single machine test, where this video and the poster above specifically talked about running against compute clusters. I don't think a single machine benchmark is going to be nearly as interesting.