One thing is for sure - if the authorities don't quickly get a grip on the technical side of this ie. what are the concentrations, where "exactly" is the ash (not what their model predicts), and what is safe, there will be many pilots out of work in the very near future......... just consider the effect if this goes on for weeks or months
As well as pilots many assciated jobs and aviation service companies will be hit and, of course, the wider economy.
On the bright side all the greenies who want to stop air travel might wind their necks in a bit particularly if they've been stuck abroad at a "conference"!!