Two years ago I finally jumped off the Thinkpad wagon to buy a Sony Z12. I have my loyalties and preferences, but at the end of the day I know that the one feature that actually directly impacts my productivity is screen resolution. The higher the resolution, the more stuff that can fit on the screen at once. The more I can fit on the screen, the less swapping between windows I have to do, and thus the less I have to interrupt my workflow. At the same time, I travel a lot, so I need a small computer. My criteria will always be the smallest usable computer with the highest resolution.
For a long time, the Sony was that computer. New computers came out over the past two years, but none of them stacked up well against the Sony. Even the Z12's successor, the Z21, wasn't much to write home about.
Then one day I read an announcement saying that Asus was releasing two new ultrabooks (you know, the Windows laptops that look like Macbook Airs), an 11.6" and a 13", and both would have full 1920x1080 screens. They'd be about half the thickness of my existing laptop, and the smaller of the two would be half a pound lighter. I was sold.
I bought the 11.6" version, the Asus UX21A Zenbook Prime.
The screen on the UX21A, particularly on the Japanese version, which ships with a matte screen, is excellent. You know that 42" LCD TV you have in your living room? This little sucker has the exact same resolution. HD video looks unbelievably crisp. The gamut range is far better than normal laptops, but not quite as good as the Sony Z12. Brightness is as good as I've ever seen on a laptop.
The processor and SSD are fast, but finding a fast computer is easy, so I'm not going to get into all that. Suffice to say that the 1.9gHz i7 is fast enough for anything you'll throw its way.
They keyboard, especially the Japanese one with the extra keys, is very good. No complaints, but not as sublime as the Thinkpad keyboard is/used to be. The trackpad is huge and responsive, with the best two finger scrolling I've ever seen on a PC. Still, I hate trackpads and am still shocked that people like them. I've used a trackpad exclusively for two years and would still much prefer the eraser-like pointing stick found on Thinkpads. Besides far better control and not having to move your hands to move the mouse, you completely eliminate the very real problem of your palms mashing on the touchpad as you type. If I have any complaint about the UX21A, it's that it has a trackpad like every other laptop. I don't expect any different, though.
Despite being a small eleven inch laptop, the speakers on the UX21A are the best I've heard on a laptop. They still aren't great, per se, but they're loud and clear. The high range is excellent and it degrades down the spectrum to having no bass to speak of.
Besides the high resolution and reasonable 5hour+ battery life, what makes this laptop particularly great for travelers is that it doesn't have to be removed from your bag when you travel. I think that subconsciously that may be the driving force behind me choosing this laptop over its larger brother.
Oh, and the other major traveler-friendly feature: its USB ports charge at 2.1 amps, even when it's off! This is HUGE. It means that the laptop doubles as a very ast cell phone / kindle / camera charger. No other laptop does this (although a few charge at .5 amps).
To make the inevitable comparison between this and the MacBook Air, the Asus has a much much better screen and speakers and can charge your gadgets. The Macbook Air can be configured with a bigger hard drive and more ram, and has better battery life. I think it's a pretty easy choice, but if you're not hardcore about screens or have bad vision, the MacBook could be a better option.