It is quite funny in this context, that there are quite a few Swiss people and politicians who want to give up the Swiss Frank or think about connecting it to the Euro, since their industry lost export orders in large scale recently because of the weak Euro. They loose millions and bazillions.
In the case of Poland the things are different of course. This country is still not a big exporter. Therefore it does not make sense to give up the Zloty in the moment.