It is already happening. In Poland the salaries among developers are getting closer and closer to salaries in Germany or UK. The reasons are that developers can

It is already happening. In Poland the salaries among developers are getting closer and closer to salaries in Germany or UK. The reasons are that developers can find a job for foreign companies (therefore local companies need to increase salaries in order to compete), but also that local companies get more foreign customers, therefore they can quote higher prices and offer higher salaries.