Just in case you missed the news, Adam Miller already announced the availability of Fedora Atomic release based on Fedora 24. You can get it from the usual place. Dusty already uploaded the same into Atlas for Vagrant. You can try it out by the following.
$ vagrant init fedora/24-atomic-host; vagrant up
As Adam mentioned in his mail, we are sorry for the delay, but we will keep improving the process. Thank you everyone for helping us with this release.