Raul, you can say that, but you could also say the say that about every single country in the entire continent of Africa. Takes these results from three days ago in Nigeria, for example:
Warri (Nigeria), 14.6.2012 -Warri Relays-
Men
100m Final A (nwi) 1 Ogho-Oghene Egwero 10.27; 2 Durotoye Adetoyi 10.27; 3 Peter Emelieze 10.39; 4 Seye Ogunlewe 10.44
100m Final B (-0,7) 1Obinna Metu 10.37; 2 Bahorou Fiacre (ben) 10.55
Those are the same sorts of times you see from African runners in European meets (where they often run). In other words, worldwide the times in the 100m haven't changed significantly in the past 70 years, if you discount the small handful of countries getting away with steroids and other PEDS. There are really only a handful of runners running significantly faster times than people did in, say, the 1950's, and with the notable exception of the skinny-as-a-rail LeMaitre, they are undoubtedly roiding, or, in the case of Gatlin, benefiting from past roiding (there was an interesting article recently about how they biopsied the muscles of former roiders and discovered that they produced a lot more growth even decades later than highly trained people who had never roided). Those Caribbean countries cheat, plain and simple. Germany has stricter testing (look how skinny their 100m champion was yesterday). Once the testers get better and level of the playing field you won't see many sprinters from the Caribbean.