Advice and comments appreciated!

Finally decided to pull the trigger and get a new rig. I'm a few years out of date when it comes to the hardware so any and all advice is appreciated! I also have no clue if there's any sort of hardware conflicts with what I've selected.
I'm on a semi-budget and $1800ish is my limit. Resolution will be 1900x1080 once I purchase a new monitor. This will be strictly a gaming rig hoping to play CoD:MW2, BF2:BC, WoW, and hopefully run Diablo 3 and Starcraft2 very well.
I'm also hoping that this gives me enough room to easily upgrade in the future by replacing just a couple of pieces.


Specifications:
Chassis Model: Special Deal Hot Seller - HAF 922
Exterior Finish: - Not Available
Trim Accents: - Not Available
Processor: Intel Core i7 860 2.80GHz (Quad Core)
Motherboard: EVGA P55M SLI  (Intel P55 Chipset)
System Memory: 8GB DDR3 1333MHz Digital Storm Certified Performance Series (Highly Recommended) (Hand Tested)
Power Supply: 750W Corsair TX (Dual SLI Compatible)
Expansion Bay: - Not Available
Hard Drive Set 1: Operating System: 1x (1TB Seagate/Hitachi/Western Digital (7200 RPM) (32MB Cache) (SATA) (Extreme Speed)
Set 1 Raid Options: - No Thanks
Hard Drive Set 2: Multimedia\Data: - No Thanks
Hard Drive Set 3: Backup\Misc.: - No Thanks
Optical Drive 1: DVD±R/RW/CD-R/RW (DVD Writer 22x / CD-Writer 48x)
Optical Drive 2: - No Thanks
Internet Access: High Speed Network Port (Supports High-Speed Cable / DSL / Network Connections)
Video Card: 1x ATI Radeon HD 5850 1GB
Add-on Card: - No Thanks
Sound Card: Integrated Motherboard Audio
Extreme Cooling: AIR: Stage 1: Cooler Master V8 High Performance Cooler (Compatible With ONLY i7 Processors)
H20 Tube Color:- Not Available
Chassis Airflow: Standard Factory Chassis Fans
Internal Lighting: - No Thanks
Enhancements: - Not Available
Chassis Mods: - Not Available
Noise Reduction: - Not Available
Boost Processor: FREE: Stage 1: Overclock the processor between 3.3GHz to 3.9GHz (Cooling Upgrade Recommended)
Boost Video Card: - Not Available
Boost Memory: - Not Available
Boost OS: FREE: Yes, Disable and tweak all of the non-crucial services on the operating system
Windows OS: Microsoft Windows 7 Home Premium (64-Bit Edition)
Restore Kit: Digital Storm Specialized Recovery System (DVD Image Based)
Virus Protection: - Not Available
Office: - Not Available
Benchmarking: - Not Available
Install/Test Game: FREE: Hot-selling game with a NVIDIA GeForce GTS 250 or above graphics card
Display: - No Thanks
Surge Shield: - No Thanks
Speakers: - No Thanks
Keyboard: - No Thanks
Mouse: - No Thanks
External Storage: - No Thanks
Exclusive T-Shirt: FREE: Digital Storm T-Shirt - Black (Xtra Large)
Priority Build: - No Thanks, Ship Within 5-15 Business Days After Order Is Successfully Processed
Warranty: 3 Year Limited Warranty with Life-Time Customer Support

I do plan on going SLI in the future, but not anytime soon. I'm assuming at that point I would need to upgrade to a 1000watt PS? I'd probably go with something from corsair, but for the time being I would stick with a 750watt unless somebody on here tells me its not enough. 
Any significant difference in ATI vs NVIDIA? I'm currently using an ATI card and have had no issues so I'd lean toward that personally.

MR's build looks good as he said, for 1900 x 1200 you want to go with a 5870/480, to go sli with 480 you want the 1250w psu, for 5870 you will want 1000w corsair.

the difference should be around $80 a year if you go with 480 sli, vs 5870 cf, just fyi.

I don't have either card so I can't tell you for a fact but I doubt you are hitting peak the whole time, also the 5870 has around 380w under load and for dual cf under load you are looking at about 560w, dual sli 480 is suppose to be around 700w.

again I don't have the cards so I have to go by what I read on reviews and the net.