There used to be times when Fidel Castro would be considered the most left-wing famous person of the Western Hemisphere. Times are changing. The U.S. progressives - of the Daily Kos type - are now vastly more extreme communists than the former Cuban leader.
Following the example of his brother Raul, Fidel gave a sensible answer to the question whether it was a good idea to export the Cuban model to other countries. "The Cuban model doesn't even work for us anymore," he said. Fidel has also criticized Mahmoud Ahmadinejad for his anti-Semitism and especially holocaust denial. However, the same criticism could be addressed to the U.S. and some European lefties, too.
It's expected that his words will help his brother Raul to promote some kind of perestroika in Cuba. I actually think that Cuba is not doing too badly for a communist country. For example, its GDP per capita is nearly $10,000, almost a quarter of Florida which would otherwise be comparable.
Obviously, if the Cuban leaders are reading the Reference Frame :-), I recommend them something very different than gradual reforms. I recommend them a Czechoslovak model of shock therapy. They may try to optimize some issues and increase the responsibility of the new owners for their companies.
However, as quick a privatization as possible - with the voucher privatization's (a fraction of stocks may be bought by every citizen, for special "children's money") being a necessary component for the companies that no one else would buy - would be greatly beneficial for Cuba's economic feature.
Now, when the leaders and former leaders already realize that the leftist ideology is a dead end, they may try to revive the enthusiasm from their best years, avoid all kinds of flavorless third routes, and build capitalism and democracy of a textbook type. With Obama in the White House, Cuba has finally received a nonzero chance to overtake America. ;-)
Update: Some sources claim that Castro was speaking about the U.S. economy, not about the Cuban economy, when he said it no longer works. I don't really know what happened so please be aware that both interpretations may turn out to be right.