For a 15.4 Inch laptop, get the Sager NP8662:
http://www.xoticpc.com/sager-np8662-built-clevo-m860tu-p-2564.html?wconfigure=yes with a GTX 260M, fastest 15,4 inch laptop around at this moment. Starting at 1400-ish dollar. Note, you
could technically put a GTX 280M in this laptop for some awesome specs on this laptop...and fry an egg on it afterwards if that's your thing.
For a 17 inch laptop, get either the Sager NP5797 or the Sager NP9280, depending on if you want battery performance (5797 has a Core 2 Duo laptop CPU) or raw power (9280 has a Core i7 desktop CPU), both pack the most powerful laptop GPU around at this moment, the GTX 280M.
http://www.xoticpc.com/custom-gaming-laptops-notebooks-laptops-ct-95_51_150.html
Can't go wrong with Sager, I'd say.
Personally, unless you plan on not to move the thing around too much I'd get the 15,4 inch version. I myself am not to fond of 17 inch laptops, because they are too heavy, far to powerful for their battery, and they ahve a huge resolution (1920x1200) which I personally find too large for such a small screen and ruins gaming performances. If you however want a 17 inch, you are probably better of with the 5797, Core i7 is just so powerful, you'll probably won't need it anyway. The GPU would bottleneck the CPU.
Standards clocks the 8662 will get over 10,000 points on 3DMark 06, and there is still some room for overclocking. It's relativly light compared to the 17 inch version, packs a punch, decent 'gaming' battery life and has a 1680x1080 screen; Great for gaming, great for Photoshopping, and if games get too taxing on you system, 1280x720 still looks really good on that same screen albeit slightly blurrier. I myself plan on getting one too (well, a european version of it anyway. Sager is just an American reseller of the laptop, originally branded Clevo).
[email protected], 4 gb of 1066mhz RAM (If anyone tries to fool you with any higher speeds on the RAM, don't fall for it, the Montevina set only goes to 1066mhz) and the usual other stuff.