I'm new here as well as new to the S3. I switched over from an iPhone 4, before that, the 3.
I just purchased the S3 over the weekend and yesterday was the first day at work with the phone, doing my usual thing, barely touching and/or using the phone.
Compared to the iPhone's, it seems that the battery life on the S3 is rather lack-luster. Literally, within seconds of unplugging the S3 from the charger, it drops down to 99%. With 5 minutes or so, it's down to 96-97%. If I pull it off the charger by 7:30am, it's down to about 35% at 6pm, and that's with it in my pocket most of the day, only checking a few PM's from my girlfriend throughout the day, maybe 10 at most! That's ridicules if you ask me.
And all of the above is after going through the Device Manager and shutting down apps that aren't needed, sync's turned off, wifi turned off, power save on, even Easy Battery Saver and Juice Defender on, and everything wiped out of the Task Manager.
Which reminds me, last night after we got home from dinner, the S3 was at roughly 56%. I woke up around 2am and just happened to notice that the S3 had drained itself all the way and was off. I tried booting it, but it just flashed the Samsung splash screen for a few seconds and went right back off. Needless to say, I put it on the charger immediately.
At any rate, I just installed the 82meg AT&T update in hopes of it improving the battery life of this thing. Other than the battery sucking, I love the phone, even more so than the iPhones!
Here's keeping my fingers crossed...