So far I have been trough 3 cycles of charging/discharging my N9 since PR1.3 - I notice improvement in power consumption. All 3 times I got to 48 hours, without even PSM mode been engaged at 10% battery level. So phone probably will go over 55 hours autonomity.
This is with always on Wi-Fi/2G, 3xIMAP always up-to-date, 10-20 emails/daily(read+write), 20 SMS's (received+send), 1.0-1.5 hours of browsing/twitter daily.