Hearthstone has just started its closed beta testing and sent out the first wave of invites from the applicant pool. To make matters more interesting, Blizzard is not holding an NDA for the duration of the beta process, so expect to hear a lot of feedback from people trying out this online card game as the beta progresses.
To get into the beta, you'll need to have a Battle.net account and choose to opt in to the test from there or through the website. Blizzard will be notifying beta participants via email, but cautions players to watch out for scams.
The studio said that it will invite more waves of players as needed and confirmed that it will be wiping all collections and progress partway through the beta period. Blizzard does not expect to do another wipe after this one, however.