The "Metro del Mare" began operating in 2001, and since we've lived here its start dates - and those of Easter Sunday - have gone like this:
2003 - 11 April (Apr 20)
2004 - 23 April (Apr 11)
2005 - 7 May (Mar 27)
2006 - 13 April (Apr 16)
2007 - 31 March (Apr 8)
2008 - 22 April (Mar 23)
2009 - 23 April (Apr 12)
Last year - when Easter Sunday fell on Apr 4 - the Regione's plan had been for the service to begin on 23rd April, however problems with the contract process led to that being delayed until June 20th.
No news as yet for 2011, and all I can suggest at present is checking back here in a few weeks: quite probably the proposed start date will again be given in the new "Invitation to tender" document, which last year they issued towards the end of February.
The 'new' website, opened last year, can be found here...
There's currently no response from the previous address... wwwDOTmetrodelmareDOTcom