Ok here I go:
My new 4s, at first it would last at least 3 days, I could have pushed the limits a bit untill the 4th day. Normal use including wifi, 3G, twitter, facebook, newspapers (I turn stuff off when ready)
After I used bluetooth the first time the fun was over. Even now when I disable bluetooth after use the battery life is a problem now. I charge every day overnight. Just like my 3GS that I used for 2 years now. After I used my navigation software for the first time on the 4S same problem as above with bluetooth so it made it worse. I disabled the location stuff thats I do not need and push etc etc. I refuse to disable everything, because it is a smartphone indeed. I close every program after use, also from multitask.
I tried to contact apple to tell them about the bluetooth problem, but thats a mission on its own so not going to try that again. I guess they will find out for themselves.
My 3GS after installing IOS5: No real battery problems, but crashing apps because of lowmem.
My lady and her 3GS: Bad bad battery problems and lowmem problems. Battery drains fast and she does not even use location services, push, bluetooth etc etc. Just whatsapp, facebook, ebay etc for some shopping of course). She goes to bed with over 50% battery en around 3/4 o clock (diagnostics tool) the phone shuts down. She wakes up annoyed because the alarm did not wake her up. Since I installed IOS 5 on her phone it of course became my problem 😉 Going for a fresh install this week.