I have had the same issue with battery drain in standby (I'm a US user). I'm assuming it is not the false standby issue as the phone promptly cut off when the battery reached 1%. I've used BetterBatteryLife and couldn't really pinpoint anything other than something was keeping the phone awake even when I wasn't using it.
I have tweaked everything, but the only thing that seems to solve the issue is installing JuiceDefender. This has dramatically improved my battery life. I'd rather not have to use it, but I really haven't noticed any impairment in the phone's performance because of this app. One thing I did learn from JuiceDefender was that my phone was attempting to autosync every 4-7 minutes. Interestingly, turning auto-sync off didn't really seem to solve the battery drain issue the way having JD running did.
I love the S3, so glad I traded in my iPhone 4. However (and this may be an Android issue, not just a Samsung issue), there is something not right with the battery management. Again, I'm guessing there is some process that is preventing the phone from going into deep sleep or is constantly waking it up. Hopefully they will release a firmware update soon to apply a permanent fix. In the meantime, I highly recommend JuiceDefender (free in the Play store). My battery drain has dropped from near 10% an hour to 2% (auto-sync off, GPS and Wifi on).