Blizzard have opened up Alpha testing, alternatively known as "friends and family" to a select few members of the public .. mainly bloggers, news outlets and youtubers/streamers.
Please be aware that, at this stage, it is very unlikely that you will get an invite, so be aware for the possibility of increased scam emails.
Blizzard have this to say:
Warlords of Draenor alpha invites have gone out to a small number of individuals for our first phase of external testing, historically dubbed “Friends & Family” for its limited scope of availability to Blizzard employees’ friends and family, as well as some streamers, press outlets, and fansites. Alpha testers are free to share screenshots and videos, stream content, publicly discuss their experiences in the alpha, and offer their feedback in the Alpha Feedback forum.
This initial wave is extremely limited, and we’ll be sending additional invites as testing progresses. In the meantime, we recommend visiting your favorite fansites for information and updates, Twitch to watch streams, and the front page here at WorldofWarcraft.com for continuing content updates. You can also check out the full alpha patch notes right here!
Please be aware that no keys are available for the Warlords of Draenor alpha, so be on guard for potential scams using invites as a lure. You can always check to see if you’ve been invited by logging into your Battle.net account at http://www.battle.net and viewing your available game licenses. You’ll never need to click on a link in an email to redeem a testing invite for Warlords of Draenor. Visit our security site for information on how to identify and avoid scams intended to steal your account information.
If you’re interested in participating in future testing phases, you can opt in here to World of Warcraft and other Blizzard game-testing opportunities. Additional invite opportunities will be announced as they become available, and we recommend checking back regularly for updates.
[edit] Worth noting that the keys given out at PAX East are for a future phase of Beta testing and are not yet active. We'll announce which phase they're active and redeemable for when that phase arrives.
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