Mid range build questions

I am ready to build a new system and after not keeping up with all the new tech I find myself with too many questions. What I am looking to build is a system (primarily gaming) that will play anything that comes out over say the next 3 years without me having to play at all the lowest settings just to get it to run. Im mainly focused on cpu/mb issues here as i realize that nobody knows how things will change on the gpu end. Im trying to get away with spending around $1,000 but im not going to worry about an extra $200 or so if it will have a real world benefit. I was originally thinking of a i7 based build, but i thought about is it really worth it for a say 5% increase in actual not synthetic gaming benchmarks for the extra cost? Im afraid i dont know enough about the differences between am3/i7/quads, etc. so im asking for help to find out what my best bang for the buck is. I do not have a brand loyalty... intel or amd makes no difference to me. I figured it was a waste of time trying to build a future proof system only to have a new socket type come out in a few years so i would have to start all over again. I currently have no graphics cards, hard drives, etc. that i will be trying to carry over so everything is wide open to me. I plan on sometimes using a lcd monitor and sometimes using my 52" lcd tv (samsung LN52A650). I was thinking about 1 gpu card to start, but i heard that if you use a large screens it is beneficial to use crossfire/sli at higher res. I know the crossfire/sli are brand specific, but is there really one that has an edge over the other as far as ease of use/reliability/stability? One area i do not want to skimp on is my mb and power supply so if you recommend parts please dont recommend a so-so part if a good one is only a little bit more. I dont know if this matters, but i am leaning toward using windows 7 when it hits retail release (in the fall of this year i think?) but to start i will be using XP. So if some combination of cpu/mb/gpu will benefit a few months down the road using windows 7 please let me know what my best bet is there. I tend not to overclock, and if i would at some point it would be pretty conservative. Well I think i covered all my major points. Thank you to anybody who helps and can teach me a thing or 2.

I'll just copy paste what i had on a previous post:

Phenom X3 720BE - $140
http://www.newegg.com/Product/Prod [...] enom%20720

GIGABYTE GA-MA790XT-UD4P - $140
http://www.newegg.com/Product/Prod [...] 6813128378

2x SAPPHIRE 100277L Radeon HD 4770 - $200
http://www.newegg.com/Product/Prod [...] 6814102835

OCZ Reaper HPC 4GB (2 x 2GB) 240-Pin DDR3 - $70
http://www.newegg.com/Product/Prod [...] 6820227293

OCZ ModXStream 600W - $90
http://www.newegg.com/Product/Prod [...] 6817341017

Western Digital Caviar Black WD6401AALS 640GB - $75
http://www.newegg.com/Product/Prod [...] 6822136319

LG Black 22X DVD Burner - $25
http://www.newegg.com/Product/Prod [...] 6827136152

Case: Antec Nine Hundred Black Steel ATX Mid Tower Computer Case - $100
http://www.newegg.com/Product/Prod [...] 6811129021

Monitor: ASUS VH226H Black 21.5" 2ms(GTG) HDMI Widescreen 16:9 Full HD 1080P LCD Monitor - $180
http://www.newegg.com/Product/Prod [...] 6824236051

Totals to $1020

Sorry, but 3 years from now, any system today will be a joke, so don't even bother there. You should still be able to play a bit beyond the lowest settings, and it still may be upgradeable, but odds are that you will just want to replace the whole thing. The list i just put there is a what is bang for buck right now.

Edit: PLEASE USE SOME BLOODY PARAGRAPHS!!!

http://www.tomshardware.com/news/g [...] ,7463.html <--- Gigabyte: Enable SLI On X58 Boards

http://www.newegg.com/Product/Prod [...] 6811119137 $74.99
COOLER MASTER RC-690-KKN1-GP Black SECC/ ABS ATX Mid Tower Computer Case - Retail

http://www.buy.com/prod/corsair-75 [...] 78325.html $114.99 Shipping: FREE
Corsair TX CMPSU-750TX ATX12V & EPS12V Power Supply

http://www.ewiz.com/detail.php?name=MB-EX58U3R $179.99
GIGABYTE GA-EX58-UD3R Core i7/ Intel X58/ DDR3/ CrossFireX/ A&GbE/ ATX Motherboard

http://www.ewiz.com/detail.php?name=I7-920 $265.99 Free Ground Shipping
Intel Core i7 Processor i7-920 2.66GHz 8MB LGA1366 CPU, OEM

http://www.newegg.com/Product/Prod [...] 6835185093 $36.99 Free Shipping*
Scythe MUGEN-2 SCMG-2000 120mm Sleeve CPU Cooler - Retail

http://www.newegg.com/Product/Prod [...] 6835154003 $4.99
Tuniq TX-2 Cooling Thermal Compound - Retail

http://www.newegg.com/Product/Prod [...] 6814125279 $249.99 Free Shipping*
GIGABYTE GV-N275UD-896H GeForce GTX 275 896MB 448-bit GDDR3 PCI Express 2.0 x16 HDCP Ready Video Card - Retail
Free Call of Duty – World at War w/ purchase, limited offer

http://www.newegg.com/Product/Prod [...] 6820231247 $89.99 Free Shipping*
G.SKILL 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Triple Channel Kit Desktop Memory - Retail

http://www.newegg.com/Product/Prod [...] 6827136152 $24.99 Free Shipping*
LG Black 22X (CAV) DVD+R 8X DVD+RW 16X DVD+R DL 22X (CAV) DVD-R 6X DVD-RW 12X DVD-RAM 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2MB Cache SATA 22X DVD±R DVD Burner - OEM

http://www.newegg.com/Product/Comb [...] mbo.186064 Combo Discount: -$20.00 Combo Price: $154.98
Western Digital Caviar Black WD6401AALS 640GB 7200 RPM SATA 3.0Gb/s 3.5" Hard Drive - OEM
Microsoft Windows Vista Home Premium SP1 64-bit for System Builders - OEM

Total: $1,197.90

+1 for Why_Me...
If you want to save some cash, then get GTX260 for $179

But even batuchka's options are good if you want to make you build cheap without sacrificing much in performance...

Is not nearly as good as the i7 and gtx 275 in my build.