It all boils down if you want to be pioneer doing it right now, pay extra for being pioneer, or wait cards and tech mature, meaning cheaper cards and stable platform and follow the pioneers. More of a choice than need in this case. At some point, having a product which you can setup an say it is ready for RT, might be a differential for selling argument. If you want to go after the tech just to have distance from all the time you need to bake lights and speed up your workflow, then you should go for it.
Now thinking as a gamer: I won’t make a purchase based only on the extra CUDA + Texture Units, simply because a GTX 1080 was already enough for me, otherwise I would have acquired a Titan xp long time ago.
As a professional: I will still wait for the hype to pass.