I would have to say no. As being shown by the Euro, tieing multiple nation's currency together, while it has some pros, can damage the currency if only a few nations take dramatic down turns. The current currency system works because we are able to ascertain the value of the different currencies and then compare them.
If there was a world currency the management of economic situations would become so complex that even more nothing would be accomplished. For example, the Euro is the official currency of 17 countries, and used in 27. Take that and multiply it even higher.