Blizzard Interactive has announced that character migrations from servers are now being offered in North America. Here you have the details:
Realm population imbalance has resulted in players on a number of realms experiencing login queues, while other realms have lower-than-average populations. Character migrations are now being offered in North America, and after localization testing is complete, we will offer the same service to our European community shortly.
Please be aware that while these character migrations are optional, each realm selected for migration will have only one designated realm to which characters will be moved. Once character migrations are ready for deployment, we will announce a rollout schedule for the migrations to take place.