hi there, welcome to the thread

battery life -> awesome if compared to most android phones like S3, S4, Htc One, and slightly better than Note 2
not sure if compared to tablet..

me.. i dont personally own one (otw dy, haha waiting for moneyyyyyy) yet but i can tell u its has better battery life than my Xperia Pro (single core 1500mAH).. my phone can only last up to 4 -5 hours heavy data usage/wifi etc etc, around 2 - 3 hours of movie watching.. this lenovo, in 4 -5 hours of browsing, u still can get like 40 - 50% battery life. (not sure how accurate but based on my experience la), for vid play back etc etc i have not tried, that u have to ask other members haha 
i am personally in middle of dilemma whether to just purchase this phone when my pay comes in or wait Asus Google Nexus 7, the new one 
 
if ur willing to sacrifice camera quality and having a pretty thick and heavy phone with SUPER DUPER battery life. then p780 is the phone, but then its better u study more about the phone before buying, cuz the last model P770 faced alot of problems. u can refer to this thread

Lenovo S890 & P770 dual core

hope i am of help to u