It's half-way through 2016 and to get Tensor Flow installed on Ubuntu 16.04 one has to register for an nVidia developer's program? Here's a hint, current LTS for Ubuntu installing a widely-used AI library should require (in total):
apt-get install tensorflow tensorflow-gpu
Seriously, why make installing a widely used library a PITA? It's only useful on your hardware, so every install further entrenches your library (CUDA)'s dominance. Talk to your lawyers, tell them to chill out a bit and then make the library available as a .deb.
Oh, and Google, you get off your collectives as well and package tensorflow too. K, thanks, bye.