All of ours get around 3hours, 3.5 max (all 2.0 Ghz 2 gig ram) with general use (wifi and BT on).. it's a fair bit less than we expected them to get.. Especially when I was used to working most of the day on the Dell X1 without needing power 
Hopefully at some point Apple will sort out the issues with the Intel power management and give us a bit more 'low useage' battery life.
Hopefully at some point Apple will sort out the issues with the Intel power management and give us a bit more 'low useage' battery life.
