I picked up the Alienware m11x before my last family vacation I have to say that it is a pretty great machine. It is not perfect, but it plays all the games in my Steam library without a problem, it is very portable, well built (no keyboard flex), and it has a great battery life. I was able to game, with the processor overclocked, for about two and a half hours and with the dedicated GPU turned off I got about six hours surfing the web.
I did have a few problems with the machine, though. The biggest one is the screen. It is glossy and the vertical viewing angles are pretty narrow, which would not be such a big deal, but both of those things just amplify the fact that the overall image quality is pretty mediocre, mostly because of terrible black level performance.
The next biggest issue is the CPU. In order to maximize battery life and reduce heat, they went with a pretty slow processor. It is the biggest bottleneck the machine has. I had to be strict about background and start-up programs, otherwise game performance would drop, even with the processor overclocked.
The m11x feels like a first generation product. I would like to see a three pound, thirteen inch unit in the future with a better screen and a CPU that matches well with GPU's performance. Overall, though, after playing games on the m11x, I am really excited about the gaming laptops that will come out in the next few years. Having a small, light, and well designed gaming laptop to tote around is just great. I almost went for one of the 10 pound behemoths, but now I would never consider it.