Ask HN: actual battery life of 2010 Macbook Pro?

Apple advertises 8-9hrs battery for the 15" MBPs. My hypothosis is that even under ideal conditions, actual battery life is much shorter.

With a 2010 15" 2.66Ghz i7 MBP, under normal development usage (a few ruby processes, a browser, code editor, MySQL) I get about 3 hours.

Under a controlled "light web browsing" environment, I get 5 hours:

* Dim screen brightness to 50%

* Turn bluetooth off, Wifi on

* Set display to never go to sleep & turn screensaver off

* Use http://http://codykrieger.com/gfxCardStatus/ to set graphics card to intel only

* Use itunes to play local music at a low volume through headphones only

* Use this script: to simulate light web browsing: http://gist.github.com/441222 . It writes a log so you know when the computer goes to sleep.

* Walk away from the the computer and wait for it to exhaust it's battery and go to sleep.

HNers -- I'd love to get your own datapoints.