Seems like the Droid 3 has a random issue where the battery charge just gets eaten up mysteriously. It also sounds like the update will address this issue.
But if your battery is always draining:
-be sure to dial *22899 to update PRLs
-low signal areas will quickly drain battery power
-corporate sync on the Droid 3 apparently drains battery (I would think the update will fix it)
-closely examine your apps, widgets, and live wallpapers. Reboot the phone and look at what you've installed that's running. Consider uninstalling and reinstalling apps until you find a culprit (don't use auto task killers or antivirus)
-the sync icon isn't constantly on in the task bar is it? Looks kinda like 2 arrows in circle
-perhaps try a home/launcher replacement like Go Launcher EX, free from market