My first thought was: “If they merge, can I now use my AA miles on an Emirates A380 in First Class?”
First things first: this is not a merger, just a joint venture. And Emirates has reiterated it has no interest in joining an alliance.
The loyalty programs of Qantas and Emirates are merging. But that doesn’t mean you can use AA miles to fly Emirates.
For instance you can’t use US Airways miles to fly Qatar Airways, a United partner (until September 14 only. Hurry.)
So for me this merger will have no effect beyond the upcoming changes it will cause to the Qantas route network. But if you have Qantas or Emirates miles, this merger will have some effect on you.
You can read all about the joint venture at qantasandemirates.com.