That was sort of my feeling too. I've been lucky so far, but I know many have been let down (Annually last year springs to mind).
I guess we shall see.
I was back on the store and randomly the PREORDER button came up again for the slipcase so I pushed through a second order as well. I got the confirmation email too, but who knows?
I continually regret not buying two copies of most PSB stuff I get - Annually last year being one such time, so when I feel like I have deep pockets I usually try to double my orders.