It looks like you're new here. If you want to get involved, click one of these buttons!
ArenaNet has announced that the "guesting" feature will go live in Guild Wars 2 after the January 28th game update. The update will also mark the end of free server transfers, so players are urged to get their characters to the server on which they wish to "live". Guesting allows players to game with friends on other servers for limited time periods and with certain restrictions.
Guesting comes with a few restrictions:
Because (different from a world transfer) we are not moving your character between data centers, you may only guest on worlds in the same region as your home world. Players on North American home worlds cannot guest on European worlds or vice versa.
You may not participate in World vs. World on your guest world. If you choose to enter World vs. World on the world you are guesting on, you’ll be moved back to your home world. If you want to play World vs. World on the world you’re guesting on, you must perform a full world transfer to that world.
You’re eligible to guest on only 2 different worlds at a time. Each time you guest on a world, that world becomes one of your eligible guest worlds for the next 24 hours. After 24 hours, you may choose to guest on a different world. You may log in to any world you are eligible to guest on as many times as you wish with no restriction.
Guesting on worlds that are full or highly populated increases your risk of being put into an overflow map.
Read the full post on the Guild Wars 2 site.