I watched, and reports were good, so I did the whole update on my P3P. All updates went smooth, but I had a hard time figuring out when the Phantom update was over? I left if for an hour, but i was probably finished much sooner. I recommend they change the light colors when the update is over. The camera light did go to solid green. The programmers appear to use "Morse Code" in the beep patterns to give them a running status. Dah-dit-dit is a long-short-short or a D, possible for "Done" Other sound patterns are other letters like dit-Dah-dit-dit is the letter L. Use a USB drive to update the Remote, worked flawlessly.
The P3P flies much better than after the last update. I quit flying after the last update because my P3P was very erratic near the ground. Changed altitudes on its on and I felt I was barely in control. Recalibration did little to improve the stability. On this update I got no requests for IMU or Compass updates and so I flew it first. Everything rock solid again. The higher altitude holds were as good as any I have ever experienced. The screen looks like it is frozen, but things on the ground are still moving. It appears so stable, a long exposure night shot would turn out great. Wind was about 13 mph.
Ipad 2 Air does get quite hot, but I'll check my settings. Auto Return to Home and land worked very good. VPS seems more stable and useful. More flights are planned. But my recommendation is do the firmware update and check it out yourself.
If you want to know the wind speed at the altitude you are flying, just fly down-wind at full forward stick. Move the yaw slightly to change your heading, (Left stick, left and right only) to get the maximum displayed groundspeed on the App screen. Then stop, let it stabilize in hover, turn it 180 degrees and go full forward into the wind. Yesterday I got 46 mph going downwind, and only 20 mph going directly back into the wind. A 26 mph difference means you have 13 mph help going down wind and 13 mph headwind going upwind. This won't work in a gusting or variable wind situation.
As a pilot, we use GPS speeds in the same way to get the true groundspeed of the airplane at any altitude. The airspeed indicators on the plane's panel may be off from one plane to another by 5 to 8 knots, so various modifications, like a propeller change may improve your climb performance, but cut down your cruising speed. Comparing one plane to another of the exact same model of the plane, one may be 8 to 10 knots faster because of various factors. On the plane I own now the wing uses laminar airflow, and giving the plane, but especially the wings, a smooth wax job, can increase cruising speed 4 to 6 knots. You use the same test flight to get your true airspeed before and after at the same altitude, engine settings and air temperature.
For your Phantom, record your maximum speed directly into the wind and directly downwind, add them together and divide by 2. So on my flight 46 + 20 is 66 divided by 2 is 33 mph. My Phantom's max speed at this altitude above sea level (1,500 feet MSL), air temperature and relative humidity is 33 mph. This will vary based on props, battery charge, weight, temperature, altitude above sea level and relative humidity of the air. I doubt waxing your Phantom will help much.
I finish by thanking DJI for the update. I look forward to some of the new software features promised like Follow Me, Waypoint Autopilot and Point of Interest. I would also like a Pan Photo Feature where you specify how many pictures you want and when you press the shutter button, the Phantom takes a picture, rotates and takes another, rotates again and takes another until all the specified photos have been taken. For public service a customizable Search Mode where you set four corners on the map and the Phantom flies the square in a pattern to photo all the area. Ideal for looking for a lost person, criminal, Phantom Fly-Away or pet in the search area. You would review the search video or stills on a big screen computer to spot the missing person. I have some other "feature ideas" for their software user interface. Return to Home altitude should be always displayed on the main flying screen, and quickly adjustable once RTH is initiated to avoid flying into obstacles that were not taken into consideration.
DJI should start a thread called "New Feature Suggestion Box to gather future software ideas from all users.