I had my iPad on standby for about 12 hours and I dropped about 8% in battery. Is this normal? Seems like it should go slower than that.
Do you have it set up to check email at a certain interval? I'd guess that they didn't have any of that turned on when they got their numbers.
Quick test results:
I turned off Push from the iPad, charged it to 100%, then at 10:30 last night, I unplugged the iPad. I checked this morning at 10:30 and it was still at 100%. Nothing like this happened before. I can't believe Push can have such a drain on a battery.
I then looked for the iPhone 3GS battery claims and saw 300 hours standby. No way the phone would make more than 2 days, the way I lose battery now while not using it, so the push+checking every 15 minutes on the iPhone really kills battery.
I'm going to leave the iPad another 6 hours just to see. I know the iPad stays at 100% longer, but the night before I dropped 8%, so I would expect around half that. Hope this helps.
Think of it this way -- if your iPad "turns on" for 30 seconds every 15 minutes to go out and fetch your email, it's going to be on for 25 minutes out of 12 hours. That's 4.2% of the published 10 hour battery life. If the standby usage is ~2% over 12 hours, you're pretty close to the usage you observed. If the time for each temporary wake cycle is 45 seconds, or if "push-ready standby" uses twice the power of regular standby, you've got it.