So really what is in this faq? It is mostly about Drones being destroyed not giving kill points. The most interesting one though for me is that marker lights can modify a roll to no existant. So the cover save can be completely eliminated and the Ld can be lowered to the point when the unit fails the Pinning test automatically. This to me is significant, not in game play but in terms of ability and what we might be seeing in the new codex.
The rest you can read here. Tau FAQ
The real issue for me is that they did a Tau FAQ to begin with. If the codex really is next, like some people are claiming, then why even do one now? Do necrons instead, as their rules are much more confusing.
With that said, this just shows us that the current order of things to come, codex releases, is going to be Necrons, Sisters of Battle, and finally Tau.