said by skeechan: The AU members have their own currencies now, but they could work closely together on free trade agreements and economic resources, pooling their efforts for economic development.
Not going to happen, since most will not pull their own weight, and have ongoing internal issues that need to be resolved like internal terrorism, civil war, genocide, border disputes with neighboors, etc.
That dosen't help either.
said by skeechan: no reason why an economic union would require a single currency
There is plenty of reason for it, it allows for simpler currency markets, promotes trade with neighbors, and allows for simpler currency regulation. However the downsides are evident.