watchOS 2 beta 3 suck battery in 1 hour

I've had the exact opposite, 9 hours so far today, and still 60% battery.

You might reinstall, and only load the bare minimum of apps, then empty out the glances. Turning off Diagnostics and Usage on your iPhone (under Privacy) might help too.

My battery life was poor on watch beta 2 and was having reboot loops and such. These issues continued with watch beta 3 until I turned off "Automatically Send" in Diagnostics & Usage (Settings/Privacy/Diagnostics & Usage) I also restarted both devices afterwards just for good measure. You could try that, though your mileage may very as this is beta after all.

I have experienced exactly the same as you. I have tried uninstalling and reinstalling the beta, turned off everything haptics, weather, feedback, etc. everything suggested in the forum. I am getting about 4 hours without any active use. Just hangs on on my wrist. Such diverse experiences reported here make me wonder. On the contrary, the latest iOS9 beta 3 seems to have improved battery from beta 2.

I've had the same issue with beta 3: fast battery drain exactly like beta 2. But after resetting all data und pairing my watch again with my iPhone the battery improved.