I have a new iPhone 4S and an old iPhone 4. I set-up the new iPhone 4S as a new iPhone, not from a back-up. My iPhone 4 went from 40% to dead overnight and my alarm didn't go off. I had my iPhone 4S plugged in, but it is going down 1% a minute for just web surfing - much too fast.
I have gone back to the stone ages. I have shut off push, shut off ping, and turned off the notification center. This improved the drain a little. Since I really don't know what the benefits of iCloud are if you only are using 1 iDevice, so I may shut it off. It's not like you can see your documents or data from a work PC, so I don't think I need any data pushed from it. I can see it being useful if you want to restore your iPhone, but not from it pushing data. I don't have mail, calendar, contacts, or notes set-up on my MacBook Pro and the iPad is a family iPad, so I don't see the use for iCloud pushing data right now.