Hi Paul and List,
while I certainly also like the idea of an open hardware board with the calypso chipset and support the fcdev3b, please note that OsmocomBB enables you to use GSM voice and SMS services from a 100% free (and copyleft!) protocol stack +drivers without any blob on a variety of calypso based hardware (Motorola C1xx phones, Openmoko phones, ...) since 2010.
Regards, Harald