If it's anything like Germany and France, then prices will drop for the first few months, then rise steadily.
I was in Germany when the € came in. It was set so that 1DM=.50€ cents. This meant it was easy to work out the rate, and everything 'seemed' half price if you were used to the DM.
Very quickly, prices did in fact double, and if you compare like for like pricewise now, it's more than double.
Germany at that time was the force in Europe, now it's probably one of the weakest, with huge unemployment rates, and businesses collapsing all over.
I was working in France in the summer of the €. It was more difficult for businesses to creep the price up because the 'exchange' rate was so complicated to work out, that prices were marked in both F and € for at least a year after the official start of the €. Prices have however shot up there too...
All in all, I'd go for the doom and gloom prediction...
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