Due to its location which is somehow far from the "world in general", it has got some specific and unique fauna and flora(Updated).
People also are quite unique in the sense that it is a mixing of Asian, African and Arabic blood.
However, you will be seeing differences from one region to other. These differences are felt from the climate and the panorama of the region, to the people's look.
I strongly advise you to visit the other links about Magagascar, they also post quite numerous pictures of the country which make you dream and increase your willing to visit this beautiful island.
This diversity is really what makes the island quite unique.