Citer:
The StarCraft II beta-test period is coming in the months ahead! If you’d like a chance to participate, now’s the time to let us know. Simply log in to your Battle.net account, and click “Beta Profile Settings” to go through the new beta opt-in process and upload a snapshot of your system specs. During this process, you’ll also have the opportunity to opt in to future betas for other Blizzard Entertainment games. Please note that even if you’ve opted in to our betas previously, you’ll need to complete this new process and upload your current system specs to have a chance to be invited.
For more information, see the FAQ -- or create a Battle.net account to opt in now. If you have an unused beta code from BlizzCon 2008 or WWI 2008, visit this site to enter your code.
https://eu.battle.net/account/management/
amen.