Matrix AI is maintaining a list of Orchestration platforms, DevOps tools, Distributed Schedulers, Cloud Operating Systems, almost all of them in one place!
Check it out at http://datacenteroperatingsystem.io/
There's a lot more out there, so feel free to submit a pull-request.
All of these competing solutions arise from different philosophies and are at different levels of maturity. If you're deciding which technology to go with, it's bit too early right now to pick a winner. However it will be prudent to keep track of all these projects including ours Matrix AI and to get your engineers test them out whenever you can.