I got it working with the UNO, so my next step was to check out the correct pins for the Fio v3, like SDA goes to D2, SCL on D3 etc.
How did you arrive at that conclusion?
http://arduino.cc/en/Main/ArduinoBoardFio
External Interrupts: 2 and 3.
I2C: 4 (SDA) and 5 (SCL).
Perhaps the latter isn't clear that 4 and 4 refer to analog pins.
Other than how serial works, there is nothing fundamentally different between the Fio and the Uno.