I had a problem that I have noticed a couple others mention on a thread or two, where the standby time calculation seems to be overlapping the usage time calculation. This made it look like the phone was in use when it was on standby. I used to test it by charging fully then turning the display off and putting it straight onto standby. When I turn it back on it would show standby 7 hours, Usage 7 hours for example, this appears to be have been a glitch in the software or a conflict when upgrading. I did a suggested restore, held off button and menu together until it went off. Then turned it on and turned it off fully with the red slide. Then plugged it directly into the wall socked and charged it from there, apparently that resets the usage calculation. Anyway left the phone overnight on standby and it seems to have resolved the time calculation conflict which is great. It shows up as a more accurate calculation now standby 15 hours usage 15 mins - before usage would always be at least as long as standby with as much extra as should have been showing as standby alone. Its been in standby now for almost 16 hours and the battery is still full! - this is the way it should be, prior to this reset leaving it in standby from a full charge the battery would reduce continually, usually to about half by now, which suggests maybe it was doing a process in the backgroud which has now ended.