I can say a few things to this..
1 - Restoring from new may or may not fix the problem. It seems some phones it does, some it does not.
2 - Turning off 3G (on your PHONE) is stupid. You bought it as a PHONE. Leave the 3G alone. Unless you're in a crap area or whatever. There is no reason to turn it off.
Battery life is SUBJECTIVE. What works for one person, does not mean it will work for you. It is also based on signal strength and how hard your phone has to work to keep that signal. You have wifi, 3g, push, fetch, etc. It will suck down battery life period. There is a lot going on in that little phone of yours. You should be amazed.
I have setup phones as new for battery issues. It seemed to have worked. Then I would get the fluctuating battery meter. I have since restored my phone from a backup and did the update. Battery life is fine. At 50% I am at 1 day standby and 3 hours usage. Push, 3G, Fetch (15m) and all that ON. No weird power saving BS here.
If your phone is burning up and dying in less than 10 hours and most of that is standby - there is a problem. Take it back and exchange it. No amount of conditioning or restoring will fix that. If your battery is draining and in only a few hours and with HEAVY USE - it could be your style of usage or a problem. Test it and see.