I have been using lots of Cortex boards including M4 boards and this is the most elegant board I have seen.
I pledged and can't wait to see the Teensy 3.0.
The Freescale Kinetis processor is an excellent choice. It's amazing to see that 64 pin part on such a tiny board. It truly is Teensy.
I hope this mean it will be open enough so I can port a RTOS like ChibiOS to it.
Teensy 3.0, an affordable 32 bit ARM Cortex-M4 board, for development in Arduino or C/C++.
I have been using ChibiOS and really like having the same RTOS on all boards.