To test the battery today we put the machine through three sets of real world situations.
One as a media movie lover on the move, a person wanting to watch HD media on a train journey or bus with two thirds screen brightness (any less and quality suffers).
Secondly as a business man, using the machine for productivity with wireless enabled and balanced power settings with a mid way (around half) brightness setting.
Thirdly as a gamer on the move, with the nVidia graphics card fully active and screen brightness up high.
We managed to wrestle 4 hours and 38 minutes from the machine before it would shut down. When watching media, the time reduced to 3 hours and 14 minutes and gaming reduced the life further to 2 hours and 42 minutes. Sadly due to the internal battery design, the replacement of the battery on the move isn't practical.