We all think Apple has crammed a larger battery into the phone than ever before, but the original iPhone which is thinner than the 3gs, and it had a larger battery. From Wikipedia: Original: 3.7 V 1400 mAh 3G: 3.7 V 1150 mAh 3GS: 3.7 V 1219 mAh And taking Gizmodos numbers... the new battery is 5.25w/hr, which = 1418ma Same size as the original iPhone. Yet the newest rumored phone has so much else crammed into it and it's thinner yet. So I'm Impressed still. But we don't have any kind of magical battery technologies going on here. Assuming Apple was able to get so much more battery life out of the 3g/3gs than the 2g, and the 3g/3gs battery was quite a bit smaller is exciting. Think the 4g is optimized on new more efficient chips, and it has a larger battery. Apple says the 3gs lasts 5 hours with 3g talk/web, I think we could easily see that go to 7hr on the new phone.