The current issue of General Aviation, the AOPA members' magazine, has an article on EASA by Martin Robinson, the chief executive of AOPA, who is on the Advisory Body. One advantage will be that mods certificated in any EASA country - like silencers certificated in Germany - will no longer need certification by other states, so in theory component costs should come down. And yes, it should mean an end to the CAA's 'star annual' racket, where owners have to pay a minimum of £600 (almost £1,000 for my R22) for a three-year C of A. An EASA C of A will be for life.
The magazine also has a full report on the trial of Donald Campbell, which has previously been alluded to in this forum.