En Masse added a new page which showing the servers status. This page displays the queue and population of each server in real-time. A server labeled “Recommended” means there’s low population meaning you’ll rarely encounter a queue while “Full” means character creation has been suspended on that server. En masse idea is to make sure everyone is enjoying TERA, and for this reason they are limiting character creation on the most-populated servers to balance them out. Throughout the Open Beta Test, they will monitor server queues and populations very closely, incrementally increasing the population cap on “Full” servers to get more players onto them. The goal here is to provide a good experience for all TERA players, not to prevent you from playing with your friends or guild.
Source: Official Site