Sometimes- I think that people who move up to 6 are then overdoing it on stuff they load on their devices to see how it runs and then leave it running. I know after I loaded 6 on yesterday, the battery 'seemed' to go away sooner... of course all I was doing was playing with it to see how it was. I wasn't just using it straight through here at work, but I would take it out every few minutes when I remembered "Oh, better check this". It was full when I went into work but over half gone just after 3pm or so. Today it was full at 9am, and it's still full. So it may take awhile to match what I was getting on 5.979 or whatever- usually 2.5 days of "normal" usage.
And to writ, there may be many differences between versions of OS 6. Going from .407 to .522 has upped by battery life quite a bit. Experiences will vary.
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