"Our costumers [for Realms] are parents who are tired of trying to act as server administrators on behalf of their kids," said Mojang CEO Carl Manneh to it24 (translated by GI.biz). "In the future we aim to offer certain profiles with mods that are certified to work without crashing, but this will still be a safe and easy way for kids and families to play Minecraft online."
With a subscription plan currently estimated at $10 to $15 a month, subscribers will have access to their own self-contained world, with "full control over who has access and their friends list." Minecraft Realms is currently in private alpha, with a "hopeful" beta planned for May.
It was also announced today that the Xbox 360's version of Minecraft will make its way to retail in April. Mojang is so very close to making a corporate headquarters out of diamonds.