I actually sent it a while ago.

Here's the Upverter image:

And, @oshpark render:

So pretty. It is $10.30 for the 4 layer board - I assume the extra $0.30 is because the castellations increase the "effective" board area from the manufacturer's perspective, but the PCB is 1" x 1" I swear! :)

Also for completion, here are all the layers.

Top (Signal):

Layer 2 (GND):

Layer 3 (3v3):

Bottom (signal):

Obviously I'll release all design files when I'm done, but it doesn't do anyone any good until its validated.

The boards are expected back around the 28th, and shipping might take up to a week. It's gonna be tight!