On my 2011 15" MBP, Chrome triggers the dedicated GeForce video card all the time, even on battery power, unless I use GFXCard Status to force it to integrated only. Safari sticks to the IGP. I haven't tried disabling GPU accelerated rendering in Chrome yet to see if it makes a difference. Also note that if you run any Chrome extensions in the background (eg: Astrid), it'll still keep a Chrome instance launched and consequently still force the dedicated video card to activate.