I got the opportunity today to compare the ASUS UX31 and the Apple MacBook Air right next to each other, which are two competing 13" ultrabooks running two distinctly different operating systems. An ultrabook is a newly coined fad term describing ultra-portable and ultra-light form-factor laptops -- think very thin netbooks.
The laptops that I tested are extremely impressive machines with almost identical features at a pricepoint of around $1,200-$1,300 in store (i5 CPU, 4GB RAM, 128GB SSD). In fact, I think every single physical port on the UX31 is available on the MacBook as well.
The UX31 is constructed from a brushed aluminium material, whereas the MacBook looks like some kind of composite aluminium, so both machines look and feel very similar. One striking feature of the UX31 is that the keyboard's keycaps are also made out of aluminium, so it seems as if the entire machine was constructed from a solid piece.
The MacBook Air is impressive in terms of hardware and feel; the trackpad is responsive and nice to use, the keyboard is natural to the touch (although plastic key caps), and having to use MacOS is not such a big deal, considering that the UX31 hosts a Windows 7 Home Premium install loaded to the rim with bloatware. Tons of ASUS applications, Windows 7 widgets, trial versions of this and that, just annoying shit. I didn't see any bloatware preinstalled on the MacBook, just the standard applications delivered with MacOS, but I could be wrong.
One thing that really stood out to me was the color representation of the displays. The colors on the UX31 looked a bit washed compared to the MacBook, which is not really a big deal, but it's off-putting, especially when they're around the same pricepoint. Both laptops are very rigid and really don't bend or flex at all, which is a good thing if you value your hardware.
I'm a big PC/Windows user (bread and butter kind of big), but if you're looking for a lightweight laptop for internet usage, text editing, watching videos, and being on the road, I have to hand my ultrabook crown - at this moment in time - to Apple. So, all in all, I think I'm going with the 13" MacBook Air for my travel laptop. (gasp)