I haven't had time to dig deep into the layout of the circuitboard, but what I've seen so far is impressive.
1. There's definitely an ICSP connector (in circuit serial programmer -- a PIC thing).
2. There's a full sized PIC18F2450 on board -- which means I can either desolder it and replace it with screw headers to attach a teensy or reprogram the PIC.
3. It APPEARS that there is hardware (capacitor circuit) debouncing for all of the switches.
4. There are holes for the LEDs to go through. Not yet sure if they are connected to power or not --- but maybe I got lucky.
Cherry MX Red switches -- who likes those?