There will certainly be an EASA PPL, from about 2012. The outlook currently is that a JAA PPL will be "automatically" converted to an EASA one, but that a national ICAO PPL issued by an EASA country will have some conversion requirements (see
EASA CRT application - Documents list and right click on the row NPA 2008 17b (from the column in the middle "number") to "View NPA". Page 162-163 details the conversion requirements).
To convert a national EASA country PPL(A) to an EASA PPL(A), in the current draft, requires only demonstrating "the use of radio navigaiton aids."
I emphasise "EASA country" because ICAO PPLs from an 3rd country will not be convertable to an EASA one unless that country has a bilateral treaty (but they may be accepted temporarily).
You certainly can't fly an
any EASA aircraft
anywhere in the world on your old ICAO PPL, you may be able today to fly one somewhere, depending on national registry rules. After 2012, your old ICAO PPL from an EASA country may lose its validity unless converted.
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