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Typically I have Safari (3-6 tabs), iCal, Mail, iTunes, and Evernote open. Generally lasts 6-7 hours. If I am playing lots of videos from websites that time cuts off about an hour.
 
I tend to get about 6 hours with my 'normal' usage (light browsing, emails, twitter etc.) - can get up to 8 if I'm just writing.
 
I can make it just about all day - using mail, safari, pages, numbers, cal, Skype occasionally. I've got 1:41 left left and have been at it since 7 something - on and off.

In heavy web use times, I'll get about 4-5 hours.
 
I get 3-5 hours with normal usage.

Lots of non-flash browser (though ads may be in Flash), 1 VM, lots of terminal
 
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