I’m using R for at least five years and always been curious about its usage in Brazil. I see some minor personal evidence that the number of users is increasing over time. My book in portuguese is steadily increasing its sales, and I’ve been receiving far more emails about my R packages. Conference are also booming. Every year there are at least two or three R conferences in Brazil.
What I learned from experience is that software choice is a group decision. It is very likely that you will use whatever your peer group uses.