I just tried a kickstart setup for the first time since 7.3 and got an error similar to the error in this unresolved Fedora bug report:
https://bugzilla.redhat.com/show_bug.cgi?id=1278260
Has anyone successfully done a kickstart setup using 7.3 on x86_64? I'd imagine this is part of QA, so the answer is almost certainly "yes," but I'm not sure where to start debugging this. I got a working system by supplying the URL to the 7.2 release instead of the current URL.