Upgraded my devices this afternoon
Netduino
(http://forums.netduino.com/index.php?/topic/5583-netduino-firmware-v420-update-1/)
PWM greatly improved (Robot goes a lot better now)
Netduino Plus
(http://forums.netduino.com/index.php?/topic/5582-netduino-plus-firmware-v420-update-1/)
50% more RAM than previous versions so less nasty bodging to reduce code size