one thing you should check is under battery usage select cell standby and if you have a high "time without signal" (usually around 50%) you should check out some of the fixes for that issue (see this thread) i've done this fix and if i am at work where no wifi exists and i have to use 3G it takes around 15-17 hours to get down to 30% right now i'm at 21hours 16minutes and my battery is at 75% most of that i've been at home on wifi barely using my phone (just checking a few emails)
another thing i found gave a small boost to battery is going through some of the apps that update my location and setting them to use wireless network location instead of gps... weatherbug and fancy widget don't need street level accuracy for location
you could also manually switch from 3G to 1x when the phone is idle (switch back when you go to use it) use the testing menu for this (CDMA only switches to 1x CDMA auto (PRL) switches back to 3G)
another thing i found gave a small boost to battery is going through some of the apps that update my location and setting them to use wireless network location instead of gps... weatherbug and fancy widget don't need street level accuracy for location
you could also manually switch from 3G to 1x when the phone is idle (switch back when you go to use it) use the testing menu for this (CDMA only switches to 1x CDMA auto (PRL) switches back to 3G)