I'd wait but then I've never been an early adopter. In this case my reasons to wait and see are as follows
1. How many movies that I want to see/own are going to be released with Dolby Atmos tracks. If like 3D has become, Atmos becomes just a gimmick in kids' films, forget it.
2. Does DTS have a similar technology in the works? I once had a receiver that could play Dolby Digital but not the DTS equivalent. It made almost every movie purchase a challenge. Never again.
3. Atmos is currently a first generation product. It will get better with time and the price of the equipment (which does include the need for additional speakers) will come down.
4. Lastly there's the WAF to think about. I'm not sure that at the moment I could sell her on even more speakers than our current 7.1 system. That will take time.
So I would wait for now.