OK, so I posted about how the jellybean update seems to have fixed the battery issue...
Only a few days later, and it's right back where it was. This phone is just brutal, I can't rely on it at all and am quite frankly fed up with it. As much as I love it (other than the battery life), I can't recommend it to anyone and regret buying it.
Today, I sent a total of 3 texts. I made 0 phone calls. I did not use the internet at all. It's on power saving mode. 8 hours and 100% battery drain.
Now it's showing 22% to MAPServiceSamsung (I have GPS off, don't know what this is, but I can't force stop or disable it), screen takes 19% despite being on for only 22mins, device idle 15%. Gallery was taking up a lot but I turned off sync altogether.
Lot of great features on this phone but unfortunately I can't use any of them for fear of the battery dying in a couple of hours if I do.