From UK Foreign Office:
15 November 2010: Alitalia CAI ground staff from 10.00hrs to 18.00hrs
18 November 2010: 24 hour rail strike from 21.00hrs on 18 November to 21.00hrs on 19 November
19 November 2010: 24 hour local public transport strike.
26 November 2010: 24 hours flight assistants Meridiana Fly. 24 hours Pilots and Flight Assistants, Alitalia CAI and AIR ONE
4 December 2010: 8 hours Trenitalia from 9.01hrs to 16.59hrs
http://www.fco.gov.uk/en/travel-and-living-abroad/travel-advice-by-country/europe/italy
Further information on strikes in Italy can be found on the Ministry of Transport website http://www.mit.gov.it/mit/site.php?p=scioperi but only in Italian.