Gaming Laptop to last under $1000 ?

I am trying to find the right laptop to buy, at home dad and don't want all the cables of a desktop, something I can move around in the house, trying to get something that will last a few years something like:

2012: can play all demanding games on high resolution (not ultra high).
2013: should be able to play most demanding games in medium resolution.
2014: most likely be able to play most demanding games in low resolution.

Mainly right now for Diablo 3, WoW (maybe if I go back) and eventual insane 3D games that comes out.

Now I know it's a high demand for the price, would prefer new but used/refurb would do too.

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What is your maximum budget?
==>A: Around $1,000 (less is better as long as it can do what I need), up to $1,200 if it's something just insane..

What country are you in?
==>A: USA

What will be the uses of this laptop?
==>A: Gaming mainly, every other thing I might use it for can be handled by a gaming pc.

Do you have brand loyalty or care which brands we select for you?
==>A: No

What screen size do you require?
==>A: Would really prefer 17"+ unless the price is below $800 so I can hookup a big screen.

What screen resolution do you require?
==>A: 1920 would be great, same thing as screen size though.

Are you looking to buy NEW or would refurbished/recertified/used be okay?
==>A: Prefer New, but ok with either.

How long should the battery last? (Under optimal conditions, no movies/games/heavy internet)
==>A: Doesn't matter that much, am almost always next to an outlet (let's say 2 hours min ?)

What games would you like to play with your laptop? And on what settings?
==>A: Diablo 3 and other demanding 3D games

What operating system do you need? (if any)
==>A: Would prefer Win 7 but not 100% req.

Is there a certain style of laptop you want? (aluminum, black, gaming, etc.)
==>A: gaming otherwise no pref.

How much hard drive space do you need?
==>A: would like 500gb min, unless there is a second empty spot which would also be insanly great for ssd boot.

Do you need any special hardware? (blue ray, webcam, specialty ports, etc.)
==>A: Webcam a plus but not a need.

Is there anything else we need to know?
==>A: As I said up there, trying to find something that will either last 3 years for gaming or can be upgraded as I go (video card, second HD, maybe even E-GPU).
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Been looking a lot for the last few days but I don't have as much time as I used to to compare 50 diff machines, GPU's, etc.., I would really appreciate the help!
Edited by Coersum - 6/24/12 at 8:16pm

I thought about that and it's true that I could easily build a great desktop for that much, but living in a 2 story house, being able to take it with me upstairs is almost a must for me (to be close to the kids). Don't get me wrong, I don't get hours on ends to play but I just want to enjoy the few that I do have to myself. Right now I have an old AMD X2 P320 with 4DDR3 and it's at the end of its use (2 years later). I'd like to find something good for now and that can "do" for 2013 at least.

I did think about an all-in-one but prices are just as high as laptop and haven't seen one with dedicated video card as of yet and that would still be quite big to go up and down stairs with

It's a nice machine for sure and a contender, I most likely can do $1100 , I just would prefer not to (depending how much I can sell our old laptop, NV53A, hoping around $250-300). Also WIDI receivers have too much lag for gaming sadly.
Edited by Coersum - 6/24/12 at 10:25pm