It would be great if we could get some accurate, or even reasonably accurate, statistics on the actual number of RepRap printers spread across the world. I do know that there are some centers of activity, or RepRap clusters, especially in the U.K.
While many of the builders are associated with a nearby hackerspace or similar organization, there are probably more individuals tackling RepRap building without local support. Some of them have banded together to form regional special interest groups, like one that I found in Vancouver British Columbia.
Others are much harder to find. For example, I know that there are Japanese RepRap builders, but I haven’t been able to uncover anything in the way of active meet-ups or events.
There is a Google RepRap map that builders can add themselves to and indicate their location/country. Unfortunately a lot of the location indicators/pins are out in the middle of the ocean – either accidentally or on purpose.
In any case, add yourself to the map and include a little bit about your RepRap activities and interests.
View Rouen RepRap in a larger map