The reality is if you are going to fully utilize the 3g iPhone and all that it offers you will need to exhibit some power management.
I don't mean turning things off, as that defeats the point of the phone. I don't want to turn off features on my phone. I am talking about charging the phone when you are in a position to do so.
If I am in the car, that is a time it can be charging even if I am using it. Same goes for work. If I am at my desk, I have the USB cable there and plug it in. I can still do everything I want with the phone, but this way when I do go out and about I am probably leaving with almost a fully charged phone, and again if I am driving somewhere I can charge up in the car.
Just doing this, I have almost zero chance of running my battery down during the day.
I would say in the case of the OP if you are running totally out by 2p every day you must be doing something very persistant for many hours at a time. Perhaps running an app like Pandora, or iPod. if you make 30 minutes of phone calls, and check mail 4 or 5 times and spent another 30 minutes browsing, there is no way you should run out of power in 8 hours like that. I don't care if push, pull, tug and shove are all turned on.
I realize we have all become used to massive battery lives in the past few years where if we plugged our phone in once a week it was enough to go.. Unfortunately with the current iPhone there are some trade-offs for what it offers. So if you want to keep yourself fully charged up, you just need to make a few minor adjustments.
I suggest that for 99% of the people, if they just put their phone on a charge at work and in their car that they would never run their battery down.