One needs to see how dependent the rest of the world is on export trade to the USA before pontificating on a switch to the Euro.
I read an article recently on real concern in Germany about the possibilty of it losing export trade to the US as a result of it's anti-US stance on Iraq.
The appreciating Euro certainly won't help Europe's trade to the US but will advantage US export trade to Euro countries (and Australia). China's currency has been and I think still is pegged to the USD.
