I wasn't so sure about the significant battery increase with the 2.1 F/W release? However after a day and a half it really made a difference on my 3G iPhone. I'm seeing about an hour increase with usage on mine. I went from 4 hrs 20 mins to 5 hrs 30 mins on Edge. About 1.5 hours of video, 1 hour of talk time, 2 hours of Safari, 1 hour of gaming. Post your increase if any.