? Cuban-Americans in New Jersey expressed cautious optimism Tuesday following the resignation of Fidel Castro as president of Cuba.

The ailing 81-year-old Castro resigned as Cuba's president Tuesday after nearly a half-century in power, saying he will not accept a new term when parliament meets Sunday.

The end of Castro's rule - the longest in the world for a head of government - frees his 76-year-old brother Raul to implement reforms he has hinted at since taking over as acting president when Fidel Castro fell ill in July 2006.

"My wishes have always been to discharge my duties to my last breath," Castro wrote in a letter published Tuesday in the online edition of the Communist Party daily Granma. But, he wrote, "it would be a betrayal to my conscience to accept a responsibility requiring more mobility and dedication than I am physically able to offer."

Cuban-Americans in New Jersey hope Castro?s resignation signals the start of change in the country.

?I?m really happy for Cuba,? said Union City resident Eliana Notarmaso. ?Maybe it?s gonna be a good start for all the Cubans here and there.?

However, their excitement is tempered by skepticism over Raul Castro?s rule. Many believe major changes are still some time away. Emelio DelValle, president and founder of the Cuban-American Day Parade of New Jersey, isn?t exactly celebrating.

?By his brother taking over, it?s a tyrant handing over power to another tyrant,? said DelValle. ?They have both been there for the last 50 years. Things they have done together will not be erased, just because one has left the scene and has given in to the other.?

That sentiment has been echoed by the U.S. government, which has stated it will not immediately change its policies toward Cuba. The Bush administration has even called Raul Castro a ?dictator-lite.?

Associated Press wire reports contributed to this story.

Additional CNN coverage of Castro's resignation