Solution - WiFi (Wi-Fi). Always ON. Wont go to stand by. Kills battery.
Just updated the 3GS to iOS 4.1 and now....The WiFi never turns off and kills the battery overnight. I use the SBSetting WiFi toggle manually when I can, but I usually fall asleep with the music (TuneIn Radio/Streaming) using it's built-in timer. Notifications is OFF. All push from Facebook and Skype are set to Off. Before I could make it stay ON by using "Insomia". That was perfect. Now I cannot turn it off.... ATimeTool, iScheduler don't work. Any ideas?
(Multitaskingdoes not drain the battery/at least not noticable. I can tell the difference when I turn off WiFi manualy)
PushDoctor Fixes Push Notificanions AND Persistent Wifi
Thanks for all your help. Your clue led me to the solution: PushDoctor from Cydia Fixes Push Notifications AND Persistent ON Wifi. Perhaps you may want to make "Sticky" of this. I've seen MANY people have this same problem.