[rayiner]

It's not particularly thin. It's about the same thickness at its thickest point at the MBA. In terms of size and weight, it's about in the middle for an ultrabook. It's battery is a little smaller than the MBA's, but not that much smaller (47 watt-hours versus 54 watt-hours). Dell's own XPS 12, which has a very marginally larger battery (50 watt-hours), gets almost 9 hours of Wi-Fi surfing at about 50% brightness.

[surge]

I've never seen a laptop actually get 9 hours. Even a Netbook or Air won't last much past 6. I think people tend to exaggerate. If you say 9 hours, I'd believe 4.5 hours.

I mean if I left it to idle for 9 hours yeah it would last at full charge, actually using it....nah. I don't think I've ever seen a laptop work at it's advertised battery life.

It's thickest point is where the fans are, its about a thin as an air where the battery is.

In either case, a Macbook Pro doesn't get any better, I've not seen any laptops that get anything past 6 hours without having a low power Atom or ARM based chip in it.

[rayiner]

> I think people tend to exaggerate. If you say 9 hours, I'd believe 4.5 hours.

I'm describing tested battery life, not anecdotal estimations. E.g. http://www.notebookcheck.net/Review-Update-Dell-XPS-12-9Q33-....

Battery life obviously depends on your usage scenario, but the one described in the article is very light. Moreover, he's using a very low brightness setting, and seems to be using wi-fi intermittently. These points are important to note because on most workloads, the display and the wireless adapter are the major sources of power draw.

The usage described in the article is:

> I get about 6 hours of usage from a full charge (or more if I leave my desk for breaks and the screen shuts off after 5 minutes, which saves battery). As I mentioned earlier, that's usually on the lowest (or second to lowest) screen brightness setting, with the keyboard backlight enabled for about 50-75% of the time, and having Firefox open with 5-10 tabs, sometimes YouTube running in the background for some music, some Terminal windows open, Steam open in the background, Skype running in the background and a few text editor windows open.

Since idle background apps should take up very little battery, this seems even lighter than Anand's "Light Workload" scripted test, on which the MBA gets 11 hours (close to its rated 12). See: http://www.anandtech.com/show/7085/the-2013-macbook-air-revi.... Anand's test is at 200 nits (80% screen brightness). The author of this article says he's running at the lowest or second-lowest screen brightness, so maybe 10-20% or 30-60 nits. Even with the heavy workload test, which involves constant Wi-Fi activity and 1080p video playback, the MBA gets 5.5 hours.

If you mimic the usage in this article, with some apps open in the background, the brightness turned down, and typing into some terminal windows, the MBA would probably get 15+ hours: http://arstechnica.com/apple/2013/10/os-x-10-9/18/#battery-b....