Cuba's interim leader Raul Castro. AFP PHOTO

For one, the acting president has made it clear the era of marathon speeches that were a trademark of the older and ailing Castro is now over.

Raul Castro, 75, also told Cubans he welcomed criticism and different points of view.

And in his first major public speech since taking over from Fidel, he called on December 2 for dialogue with the United States, with Washington responding by saying the communist state would first have to adopt democratic reforms.

Over the past decades, Raul Castro, who is also defense minister, has earned a reputation for pragmatism, but critics point out he can also be a ruthless hardliner.

Hailed by the Cuban regime as the deserving heir of the longtime revolutionary leader in whose shadow he has lived for almost half a century, he was "provisionally" deputized on July 31; four days after his older brother underwent intestinal surgery.

Authorities have given little information about the 80-year-old president's condition, but no longer insist he will eventually be back on the job, while Cuba-watchers believe the post-Fidel era is already well under way.

In the almost six months since Raul Castro has led the government, he has kept a fairly low profile, in sharp contrast with his brother who thrived in the international spotlight and involved himself in the most minute details of life on the Caribbean island.

In a speech to students last month, the younger Castro invited reflection and criticism, and said the time was coming for the old guard to pass the torch.

"He told them he wants to hear different points of view; that is very 'un-Fidelista,'" said Brian Latell, a former CIA analyst who has written extensively about the Castros in his book "After Fidel."

But he claimed the younger Castro also had another personality - "Raul the Stalinist, the terrible," which he said could re-emerge at the first sign of trouble.

Raul Castro admits he is quite different from his charismatic brother, but stresses he is committed to the continuation of Cuba's revolutionary system under the auspices of the communist party.

He recently let it be known he would not monopolize the stage.

"From the first moment it was established that I would not be giving all the speeches," said Raul, who is aided by six top officials the older Castro hand-picked to assist him.

Raul Castro is said to have two big passions in life, the revolution and his older brother.

Born on June 3, 1931, Raul Castro studied economics, but joined the insurgency without completing his studies.

He was jailed alongside his brother following their 1953 assault on the Moncada military barracks in a first, failed attempt to topple the dictatorship of Fulgencio Batista.

After their release, the two went to Mexico and eventually returned by boat to Cuba with another 80 rebels in 1956.

When the revolution led by Fidel triumphed in January 1959, Raul Castro became second-in-command and head of the armed forces, which he has since shaped into a powerful, complex institution.

Strapped for cash after the 1991 collapse of the Soviet Union, then Cuba's main financial backer, the Revolutionary Armed Forces under Raul Castro have formed a series of money-churning businesses, including a tourism corporation that runs a domestic airline, hotels, retail outlets and marinas.

"If Fidel has decided Raul is capable, it means Raul can be the leader," said Lourdes Morales, 63 a bathroom attendant at a Havana hotel.

She proudly proclaimed the revolutionary slogan "Until victory always," adding: "whether Fidel is dead or alive."

Raul Castro is assisted in his duties by six top communist officials.

All are members of the Central Committee of the Cuban Communist Party (PCC), in this one-party state.

They are:

Carlos Lage, 55: a vice president of the Council of State, he has played a key role in economic reforms that helped Cuba recover from a deep crisis in the 1990s caused by the collapse of the Sovie Union, then its main financial backer.

Jose Ramon Machado Ventura, 76: an orthodox communist, he heads the PCC's internal affairs department and is responsible for supervising the application of education policies.

Jose Ramon Balaguer, 74: the minister of health, he is also considered a hardline communist.

Esteban Lazo, 62: an economist, he is the head of the PCC ideology and foreign affairs department.

Francisco Soberon, 62: the president of the Central Bank.

Felipe Perez Roque, 41: Cuba's foreign minister.