I think that few cold start cycles won't fix it. My is 2005 with 6500 miles, and on 21st March I'm taking her for a big service ( engine oil and brake pads change, throttle bodies balance etc.) - the guys at the dealer told me that they will also fix the odometer, so in two weeks I'll be able to know more about this failure.
"ME TOO!
My '09 has about 100 miles on it, now the speedo needle won't move. I can toggle through the trip meters, and the ODO is stuck at 10 miles. My dealer is 100 miles away, I don't want to have to take it in if I don't have to. Is there a chance it will reset and work after a couple cold start cycles? Thanks."
Before going to your dealer check if the road speed sensor is securely fit and connected to the circuit.