Version 0.9 adds a few new firmware features and accompanying AltosUI changes, along with new hardware support.

Support for TeleMetrum v1.1 hardware. Sources for the flash memory part used in v1.0 dried up, so v1.1 uses a different part which required a new driver and support for explicit flight log erasing.
Multiple flight log support. This stores more than one flight log in the on-board flash memory. It also requires the user to explicitly erase flights so that you won't lose flight logs just because you fly the same board twice in one day.
Telemetry support for devices with serial number >= 256. Previous versions used a telemetry packet format that provided only 8 bits for the device serial number. This change requires that both ends of the telemetry link be running the 0.9 firmware or they will not communicate.