Oh, I'm sure you can get that - if you throttle the CPU to 20% of its capacity and turn the screen brightness down to minimum, set the disk to sleep after one minute of inactivity and the screen to go blank likewise.
In other words, you'll get 17.6 hours of use if you make the i7 function like an anemic i3. Yay.
I'd like to see battery life expressed in real-life, pedal-to-the-metal situations. If you're a programmer, you're going to be taxing those 16GB of RAM and probably the disk as well. I want to know how long I will be able to work, not just look at a dimmed screen.
But that'll never happen. Nobody will like to publish those numbers, they're too weak.