Originally Posted by apjans
That doesn't sound normal to me at all. I don't remember what my droid x got in sleep mode, but my galaxy nexus generally only loses about 10-15% overnight when not charging, and I consider that phone to have pretty bad battery life.
Perhaps there is an app that is preventing it from entering sleep mode. There is an app called cpu spy that will tell you if and how long your phone is entering sleep mode.
Depends on the reliability of service in a persons area also. A phone can be in "sleep mode," but if the signal is not good, then the phone will continue to drain searching for service. I know many people that put their phone in airplane mode, when they go to sleep.
For me, I've had a 10-15% drain (the above mentioned drain was only 16%) for both my EVO and Photon, so it really doesn't sound out of the ordinary. But, I will preface that by saying that, I do have emails pushing directly to my phone (constantly) and data turned on all the time, as well as other apps that run in the background.