Anyone who registers to try out the game ahead of launch will be eligible to become a beta tester, though not everyone will be asked to participate. It also isn't clear when the testing will actually begin, though the company has said timing and details of playtests will be provided to those who register at a later date.
The Elder Scrolls Online is the first title in the popular franchise to venture into the MMO space. One of the more interesting features that Zenimax Online has promised will be part of the game is the introduction of "Megaserver technology". This means that you won't have to make sure you and your mates select the same server or shard when starting the game in order to play together, but will instead be able to constantly interact through one connected world.
The game is currently only planned for release on PC and Mac in 2013, though we have heard previously that a console version hasn't been ruled out. It's also worth noting that it hasn't been announced whether the game will require a subscription fee or not.