Nothing surprising that Nokia 808 PureView with that smallish battery compared to Android phones can still top most of the other phones with the less battery consuming Symbian on board.
The final endurance rating you see above is calculated followingly.
The final endurance rating for the Nokia 808 PureView is 34 hours. That rating indicates how long the phone will last if you do an hour of 3G calls, an hour of browsing and watch videos for an hour each day.
Video playback is one of 808′s strengths with humongous gap to Lumia 710. Surprisingly where 808 performance is lacking is the talk time. That said 808 PureView has been widely reported to have one of the best call quality and reach out there, so you might be at least partly paying for that performance.
As a whole 808 PureView should have no problems after couple of battery cycles to last one day even with the heaviest of use.