Bungie and Blizzard Authentication Login can now be linked for Destiny 2
Those who pre-ordered Destiny 2 can get a redeem code within 3 days to participate in the Destiny 2 PC Beta test. As of July 12, you can now link your Bungie and Blizzard Launcher authentication login (details here).
Just click the login link at the top-right of the Bungie website, and you will see three options: PlayStation Network, Xbox Live, Blizzard.
You can pre-order Destiny 2 for Early Access Beta code here.