Elthraim: We must all look pretty funny, frantically searching the forums for this 30 minutes after launch (while our games are all downloading)... :)
To meonfire's point, even though the Digital Deluxe Upgrade DLC shows a price for me, if you look at the bottom left of the DLC listing, there should be a tiny checkmark. I looked at DLC's I own for a different game and it shows that checkmark (and the price, confusingly, since I already own them) for the ones I own, and no checkmark for DLC's I don't.
So, if you ordered the game before the (very) recent official release, you will get the deluxe edition.
You're right. Mine also has the checkmark, but still the price. Maybe it's like that to buy as a gift? On the upgrade page it now also shows as "In Library".
Also strange; clicked "Go to library" opens the strange game browser that you normally don't get and then if I search Baldur's Gate 3 it says Incompatible. Then clicking it opens the non-deluxe game-page and offers the install, but still the old client.