Strange that I seem to monopolize this thread. But I read that USAC-CGT added a strike on Thusday 2 June (tomorrow). It seems to be the biggest ATC union.
I know because several European airlines already cancelled flights.
AF is currently quite conservative in cancellations, but the number of cancelled flights seem to be increasing:
http://www.airfrance.fr/FR/en/common...air_france.htm