On Guild Wars 2 Worlds

On the verge of the first Guild Wars 2 beta event, the ArenaNet Blog offers new details on how the game worlds will operate in the upcoming MMORPG sequel, and how players will be allowed to transfer their characters. Here's word:
While you can change your home world, there is a limit of one world transfer every seven days per account and a charge of 1,800 gems for each transfer. A world transfer moves all of your existing characters to your new home world. Any subsequent characters you create will also play in this new home world.

When Guild Wars 2 launches, you will also have the option to play with your friends on another world with our free “guesting” feature. With guesting, your characters can play on any world where you have friends—with certain restrictions. For instance, you will not be able to participate in WvW while guesting.