I'm Matt, KC2O, from San Francisco, and I've been interested in developing a platform for a low-cost, low-power packet-based emcomm BBS system.
I have a fair bit of experience with PIC and Arduino-based projects, but neither of those seemed to be sophisticated enough to do what I think is needed. Combining RaspberryPi with a TNC-X (or customized equivalent) will be perfect.
(Incidentally, I just rebuilt the AX.25-including bootc kernel to support my wifi usb dongle, by following Dominique Gallot's excellent notes here: http://www.gallot.be/?p=150.)
While I have a fair bit of experience with Linux, I'm new to packet, and look forward to getting help from this group.