Version 2.5 of the ArduCopter code is now available in the AP Mission Planner and in the downloads area!

Enhancements:

1. The first ArduCopter code release optimized for the APM 2.  Leans and drift should be much reduced or even eliminated for most users.  This was accomplished through a number of core improvements to the DCM implementation by Tridge like this one and this one.
2. Loiter and waypoint following should be improved due to a D term bug fix, some tuning and the improved DCM performance mentioned above.
3. On start-up, the yaw heading is updated with first successful mag read (so you should no longer see the slow rotation from north to your actual heading).
4. Increased output rate to ESCs to 490hz.  This update rate is also user selectable using the new RC_SPEED parameter.
5. hexa copter stability patch bug fix (should resolve slight flattening when pitching forward and accelerating very rapidly).
6. improved baro filtering
7. fix to dataflash logging of Mag heading
8. addition of H1 swash plate type and bug fix for proactive yaw compensation for collective pitch changes for TradHelis.