I was thinking in this question very much and I believe I have the answer.
The importance of Haiti it is the following:
(1) It was the first non European country that broke free from colonialism. Long time before East Asians, East Indians, Middle Easterners and Hispanic Americans got rid of European countrol, Haitians won theirs independence fighting against the French army, nothing less.
(2) It was the first state established mainly by South Saharan people.
(3) It was a land that inspired and helped economically in the struggle for the Independence of Latin America.
(4) It was the first country that recognized as official an African religion: Voodoo.
(5) The independence of Haiti marked a signal of worry in the slavery business in the United States. They show the world Blacks slaves could be free and have the right to be. In some sense, it was the first step in the political rights movements in the U.S.
Haiti has a very troublesome independent life, that still is going on, but the impact of the Independence is what can't be forgotten.