UPDATE 9/8/2009: Aion open beta keys are now available to all North American Fileplanet users, including those with free accounts.
NCSoft’s misleadingly-titled “open beta” for Aion is not open at all. It requires either a pre-order (which costs money), a Fileplanet subscription (which costs money), or a closed beta key (and if you already have a closed beta key, this article isn’t relevant to your interests).
I discovered this only after downloading the 9+GB (gigabyte) “open” beta client via BitTorrent and installing the client on my computer. Learn from my mistake: Do not download the Aion open beta unless you already have an open beta key. Avoid wasting bandwidth on NCSoft’s false advertisement/bait and switch, skip this beta, and wait for a trial. Better yet, play an online role-playing game by a company with scruples.