I feel your pain. I did escalate the problem to Apple via a phone call to them. Here is what occurred:
1. Suggested to turn off automatic mail to isolate whether or not email looping was occurring.
2. Suggested to turn off GPS to all apps which simply do not need it. i.e. Angry Birds simply doesn't need it.
3. Suggested to turn off all unused apps which may be misbehaving. (from multi-tasking area)
4. Suggested to go to your carrier's web site and locate the data usage area for YOUR phone. Then look at that detailed information and note any times where cellular data transfer should not be happening while you are in on a Wifi connection (like at home). If you see, like I did, tons of data transfer on cellular when I was asleep, then that confirms that issue. Apple has ways of correcting that issue.
5. If, after all that, you have some concrete information to share with Apple, they can send you either an sms or email with a link which will provide your phone a separate profile which can then later be used by the engineering staff of Apple to diagnose the exact cause of the problem. But after I performed 1-4 above the problem stopped. One of those was causing my problem. But Apple did want me to add a profile so I allowed them. It is now being evaluated but it doesn't look like I will have to have more support as my problem went away.
6. The iPhone 5 has a built in system of recalibration of the battery status system. It has been shown that, when a particular phone has a badly calibrated battery system that it will take a number of days for it to reset.
My phone is now usable all day. I slowly added back the items I turned off and left off those GPS location services to those apps which "I" determined dont need it turned on.
I totally empathize with everyone's problem. Trust me when I say that Apple Engineering is working on this and have already fixed a few of these battery related problems in the 6.0.1 system update even though it wasn't advertised. I did not notice any change to the battery issue when I upgraded to 6.0.1.
I'm retired so I had the time to spend on this. Many of you don't have that time so I hope by documenting these here you can benefit from the time I spent correcting this issue. In my opinion, individual "Genius" people at Apple stores is nothing but a crapshoot. You may get a good one and then you may not. Escalating it via the Applecare number is a more productive option. When you eventually get escalated to the people I worked with you are dealing with personnel who deal with these issues all day long. My last contact with Apple support ended yesterday which is why I am documenting it now.
Cheers
Edit: Forgot to mention one other item:
7. Turn off iCloud backup. When the iPhone is first being used and you have configured your iPhone from an old backup it just makes sense that there will be a lot of data transfer to the cloud when it is being backed up to the cloud the first time. That can take days to do and maybe longer. For me, I had restored from my iPhone 4 which had over 700 apps on it. The backup took over 8 gig of space in the cloud. So, that could have had a huge factor when you first use your iPhone 5.
If I remember anything else I will edit some more. (grin)
Message was edited by: Three60guy