All the EU 'accession' countries have very low GDP per head (some as low as $5000). Many of those countries have small populations. The two largest, Poland and Hungary, have already attracted new loco operators (Air Polonia, Wizz Air and Sky Europe - yes, I know they are from Slovakia). Markets there are likely to be saturated for a while, but I'm sure Ryanair will pounce just when things are getting difficult for the new entrants. That won't be for a few months yet............