Oops - apparently I'm suffering from a similar issue...
Did a clean upgrade. Battery discharged in 2-3 days. Changed launcher, lasted 2 days.
Battery use states --> Device Idle 47%, Android OS 34%.
There is literally nothing turned on. No wifi, no 4g, no gps [airplane mode]- nothing. It sat in its case for 2 days. Apparently it's busy doing *something* but prefers to keep its activities secret.
I did another power reset and am charging again. Before ICS, the unit could sit for a week or more, fully charged.