The speedometer will show as an option after mixing in the video player... once you tap the "Add Speedometer" button the speedometer is rendered in the background and the new video with the speedometer is place in the iPhone video library.  So you will now have 2 version of the video .. one with, and one without the speedometer in the iPhone library.  

We have the full release of telemetry coming out soon .. the process is just a little longer while in Beta :).