My third full charge cycle, I got 33 hours with moderate use.
Even had a hard time killing the battery when there was only 3% left. Still was able to watch about an hour of HD video on YouTube.
My primary goal with the this phone is to be able to use the phone in any manner I want for a full day without having to worry about turning off WiFi, Bluetooth, screen brightness, etc. Seems to me even with heavy use, the RAZR MAXX will never have a problem lasting the full day.