A price increase is expected but it's just temporary.
In order to be allowed the right to adopt euro, the countries had to follow very strict rules for about 5 years (such as much reduced trade deficit, no inflation, no devaluation relative to the other EU members).
So, it's definitely serious responsible stuff.
What's interesting is that the UK has covered this as their major story just like the rest of the EU countries. If most of the UK trade is done with Euro countries, it's going to be very difficult for them not to react to whatever the European Central Bank does. Imagine: they would be completely powerless (not having adopted the Euro) but if they were member of the euro countries, they would at least be able to influence its course.

When I got my first 20 and 50 euro notes, I had a strange jubilant feeling: Yessss!! (first reaction).
This is the single most obvious, visible event that touched every person living in Europe and that reminded us of where and who we are.
All the other events (such as treaties) always seemed quite remote.

Raoul