Why do you think this is about the hardware at all? Most of the savings are down to software (try Windows or Linux on the Macbook Air). It requires lots of hard work to change the kernel to make better use of sleep state and to reduce CPU utilisation in apps.
The reality is that Apple cares about battery life, because they know users do, they work constantly on this. Numerous Apple announcements talk up battery life improvements, they are clearly very aware of this issue.
I've never got the impression that that Microsoft does care very much about this issue, in fact their kernel doesn't even sound like it gets much development in the core functions (it's all about fixing bugs and adding features).
The reality is that Apple cares about battery life, because they know users do, they work constantly on this. Numerous Apple announcements talk up battery life improvements, they are clearly very aware of this issue.
I've never got the impression that that Microsoft does care very much about this issue, in fact their kernel doesn't even sound like it gets much development in the core functions (it's all about fixing bugs and adding features).