The reservation process seems broken, at least for me. I registered yesterday and got an email a few hours ago saying to go ahead and pre-order now, before everyone else can do so at midnight. But when I click on the link to pre-order, and go through the whole process, at the very end it says "Our apologies. We could not find a reservation associated with the email address you entered".
But the email address I'm logged in as is the same as what I used for the reservation, and the same as the address to which Samsung emailed the reservation confirmation.
I chatted with customer support and they say their team will look at the problem sometime tomorrow.