So the article on the main page regarding Dell's laptop got me thinking I need a new laptop for development. I'm currently still using a 2008 Lenovo X61 when I'm away from my desktop. I initially chose this laptop back then as it would be pain free when it came to drivers, and that it was.
I'd like something a little bigger - perhaps 14"? Ideally quad-core, and can handle 16GB of RAM as that would allow me to replace my desktop with it.
Other than some Macs, the screens all suck. I am fond of Lenovo other than the screen resolution - matte is important to me. I swapped my 2007 vintage T61 for a T430s. Everything works fine out of the box. I did replace the DVD drive with another battery since this model doesn't have the stick out batteries like other models do.
The specs are a dual core/quad threaded i7-3520M, 16GB of RAM, 500GB 7200rpm spinning disk and a 250GB mSata SSD stick. I got the version with a Thunderbolt port although I haven't tried using it. IIRC you have to get the i7 and no Nvidia to get Thunderbolt. Memory, drives and msata are cheaper anywhere other than Lenovo.
For Lenovo stuff I highly recommend the forums at notebookreview.com.
I am using a 17" Sony Vaio Z series with and SSD and 1920x1080 screen for a long time. Quite happy with everything. Sony laptops work better than expected with Linux, though this is by chance rather than Sony's support. Next I ll check one of the ultrabooks and Dell XPS Sputnik
You could get a 13 or 15" Macbook Pro (Not retina) and install Linux on it. (I use OSX with Macports which is fine for my needs but the fresh install of Linux is still an option). I really like the Apple Hardware although I am becoming gradually less enthusiastic about their attempts to make OSX more like iOS.
I could never get the trackpad quite right, and the battery never lasted as long as it did with OS X. My travel kit is dual laptops. One Linux and one Mac. So far the T430s with 16gb RAM is looking very close to ideal.
I've had positive personal experiences and anecdotes from others about the Intel Core i7.
I haven't seen a laptop that's expandable to 16GB. But I also don't usually look higher than the middle of the market when I'm laptop shopping, so you may be able to find one if you're willing to pay a paying premium price for it.
Don't be afraid of a machine with a too-small hard drive or memory. Upgrades for both are cheap. CPU, GPU, and monitor, on the other hand, are usually difficult or impossible to upgrade in a laptop.
If you don't have a specific use for a graphics card, consider going with a machine which only has integrated graphics. It will save you a lot.
The HP Envy 17 is expandable to 16GB and the Lenovo T430S is as well. I know this ecause I use both of them.
The HP Envy is a beautiful machine, but it lacks the drivers for Linux. I am currently using Linux in VMWare because of the lack of drivers. Especially the Graphics Card Switching driver. That is the one I miss the most, because it makes my battery last for 5-6 hours.
I know this is a weird suggestion, but the best combo for me is a Macbook (air or pro) with Parallels running a Linux VM full screen.
Performance is shockingly good, you don't have to worry about drivers, and you still get access to a bunch of nice OSX things inside the VM (Retina res, keyboard shortcuts for volume, Mountain Lion's speech dictation, etc)
Plus, you get that sweet sweet Apple build quality.
I would personally recommend a Samsung Series 7 15.6" laptop. It has a super thin bezel around the screen so it form factor is more like a 14" laptop. It is less than an inch thick, and is very portable. Mine has an 17-2675QM quad core in it, and it is expandable to 12gigs of ram(4 gigs is soldered on the motherboard). It also has a radeon 6750m in it. But most importantly, it has a 1600x900 MATTE display. I run only ubuntu 12.10 on it, and it does take some configuration out of the box to get set up right, but a quick google search is all it took. Few minor things don't work on mine, but overall I am extremely happy with it.