As we all know, the TensorFlow is very powerful and mature deep learning library with strong visualization capabilities and several options to use for high-level model development. PyTorch is still young framework which is getting momentum fast.
I strongly suggest CS and IT researchers/engineers learn both of them.
Tensorflow will be a good option if you are developing models for production or on mobile platforms, maybe in the future for large-scale distributed model training. Because it has good community support and comprehensive documentation, it is easier to find answers and get helps online.
Well, PyTorch is a good fit if you are doing research or your production are not very demanding.
Personly, I think Pytorch has better development and debugging experience.
C. Cui's Blog 