He, he,
I went there in Sep 2004. Hopped 7 islands (Tahiti, Moorea, Huahine, Raiatea, Tahaa, Bora Bora and Manihi) and just loved it.
The islands are pretty small (you can drive around say Moorea in less than an hour), and they are much older that for example Hawaii. As a result they all have atols around them. In other words, a typical tahitian island is a central volcano (or more frequently two) encircled by a ring of tiny sandy islets on a coral reef (motus). The lagoon between the main island and a motus contain a spectacular wild life. You can swim with sharks, rays, and all kinds of fish.
With time the volcanos are sinking under water and all that remains is just an atol. The Tuamotus archipelago contsists of many very old sank volcanos including Rangiroa and Manihi. It and unforgettable experience to be on and islet only a couple a hundred feet in diameter in a muiddle of the Pacific. The atol is a ring of a couple kilometers and it is not continous, it's a chain of islets. You can walk between them as the water is very shallow.