Just wanted to share this info. I have 3g ipod touch 32 Gb. Recently i had 4.0b1 installed on it. I was amazingly surprised when my battery was going down from 100% to 55% during 1 hour of wifi surfing(+music). I thought my battery is fcked up. Then i have restored to 3.1.3 and my battery lost like 5% or less during the same time of surfing + music.... So i dont know what is wrong with 4.0... but it eats battery like crazy.