Just my two cents here, I noticed a lot of people mentioning the screen size.

For programming, a big screen is a big plus, since you have more overview, which means far better sight on whatever you're programming at the moment and far less scrolling.

But if you will make your an important workstation the following years, I would also advise for a good resolution. I have a 15,6" laptop at the moment with 1920x1080 as a screen resolution, and this was an important factor in my purchase. A screen of 13" or 15" won't really matter if they have the same resolution, you'll have the same overview. So if I were you, not only get a screen that's at least 15", also make sure it's at least qualitative, since you'll be staring at it a lot the next few years

First of all, a 13" laptop will be annoying to program on. That size screen might end up being too small. More screen real estate is better, it will be much easier to get things done.

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If I were you I'd go 15". The integrated chipset should be fine, you have a lot to learn before you get into higher-end graphics.

In principle I agree, however, screen size != screen real-estate. There are plenty of 15.6" laptops out there with the same 1366x768 resolution you'll find on many 12"-13.3" notebooks -- even some as as small as 10.1".

You want a combination of resolution AND screen size to provide enough pixels which are large enough to not strain your eyes. You can find a few 13.3" notebooks in the range of 1440x900 or 1600x900 -- notably the 13" macBook Air, and there's a Sony Vaio that I'm aware of. The MacBook Air is probably out due to rather old components inside currently -- however its rumored that a whole new wave of mac products will be launched alongside OSX 10.7 very soon, including new Airs, Minis, and MacPros.

On the PC side, its worth noting that AMD's new laptop platform, based on the Llano Fusion APU will be on shelves within the month, possibly weeks -- early reviews are promising -- with CPU power competitive with lower-end Intel CPUs and GPU power comparable to low-medium-end desktop GPUs (400 shader cores, plays many modern games at native resolution at playable framerates). The best part is that you can expect to see these machines appear for $600-$800 probably, and with battery life topping 8 hours.

If its not a pressing matter, I would recommend waiting a month or so to see what's new -- normally you can't play that game with PC hardware because it will always be "one more month", but in this case the market shift is going to be pretty dramatic, and the schedule is known.

Easiest thing to look for is a dedicated gpu. No integrated.
I would also look for a duel core about 2 GHZ+. Quad is over kill.
Also, if you plan on using linux, then get one with NVIDIA, not ATI/AMD (GPU)

I have a Sony Vaio with Core 2 duo running at 2 GHZ, 6GB of RAM, ATI HD 4650 (like I said, get an NVIDIA) with native resolution at 1600x900. Don't know the screen size, but bigger than 2 wii motes with motion plus diagonal. Program on it all the time. Runs WoW in Ultra (besides shadows) perfectly. Paid $1k for it ~2 years ago, something better for cheaper is available now a day.

Supposedly, if my computer is running something non gpu intensive, it will fall back to integrated. So you can look for a laptop with that. Will save power. Not sure if mine actually does that or I just read something wrong, but they are out there.

Just look for specs like that and it will be perfect.

If you pay more than a grand for a laptop, that is a bad choice. Blah was going to comment on the person who suggested a Mac but I will leave that for another day.