> Which GPUs they offer and how much, nobody knows.
They might not offer GPUs at all. It may be that Google is planning to build a cloud using their own proprietary "Tensor Processing Unit" chip designed for TensorFlow (https://en.wikipedia.org/wiki/Tensor_processing_unit)
TPUs are only useful for prediction, not for training.
Unless I missed something, whether or not they are for training or inference has not been clarified.
They mention that they use them for inference in one of the TF papers; also the focus on per watt efficiency rather than speed/memory means it's probably for inference.
Which GPUs they offer and how much, nobody knows.