Martinique is "just" a French overseas department using the same registration system than the Metropolitan France. Its department code is 972, but it doesn't mean anything any longer, as even someone living in Alsace or in Normandy can have this code on his/her plates.
Only New Caledonia, French Polynesia, Saint-Barthélémy, Saint Martin, Saint Pierre and Miquelon, Wallis and Futuna, French Southern and Antarctic Lands and Clipperton Island use alternative systems.

Anyway, "your" site gives data in an illegal way: the specs and make of the vehicles related to the plates should be kept private by companies that can access to them and only used for internal (statistic or commercial) use. The French law (fr) is clear about it: only entitled people should see these data, not anyone browsing the Internet.
"Your" site incurs a 300.000 € fine (fr) for doing it that way, and you too by using these data in a website fully accessible to all...

The only public data are in fact the last letters given as plate number (see here, 2nd line, 3rd block, with "Chiffres" as title). All tables or figures you can find in the Net about 2009+ French plates should come from there or from observation in the street. But even that last case is dubious when displayed on the Net, I think, as it could certainly be seen as dissemination of personal data by some disgruntled people...

Keep in mind that I just list the laws that apply for now, this doesn't mean that I agree with them. Nor that I don't

@antp: even if the server is not in France (or is it?), I'd advise against including this site in the link list to avoid any potential trouble. Until next law change.