Critique My Build...Please!

Build Type: First Time Build/Budget System

Approx Component Budget: (including OS, excluding monitor) $1095 USD

Component List: (all prices pre-rebate--post rebate should round out to $1000)

Case: Antec Twelve Hundred (w/ plans to add two additional Tri-Cool 120mm fans in Jan.) $160
Power Supply: OCZ GameXStream 700W PSU $105
Motherboard: MSI 45 Platinum HC Edition (w/included Thermaltake V1 CPU Cooler) $214
CPU: Intel Core 2 Duo E8400 $187
Graphics: Powercolor AMD Radeon HD 4830 512 MB GDDR3
(planned upgrade to crossfire configuration in late Jan.)
RAM: 4GB OCZ Reaper PC2-8500 (DDR2-1066) 5-5-5-18 @ 2.1v $68
Hard Drive: Western Digital 500 GB Caviar Black, WD5001AALS $70
(planned upgrade to 2 TB RAID in Feb)
Optical Drive: LG Black SATA 16X DVD-ROM, 48X CD-ROM w/lightscribe burning.
(planned upgrade to additional drives in near future, still undecided on Blu-Ray)
OS: Vista Home Premium 32 OEM $100
(planned upgrade to Vista Ultimate retail or Windows 7 retail in future--depending upon how long system configuration remains static before WGA requires new product key)

System purpose:

Introduction to overclocking, moderate gaming, (occasional FPS w/mostly RAM-intensive grand strategy), eventual use as a personal DVR (so moderate video encoding). Planned re-use of some parts (case, graphics, hard drive, power supply) for a re-build on release of Intel's next mainstream chipset (X58 and Core i7 seem a bit pricy atm)

General feedback requested:

Comments on pricing, part selection (did I purchase anything junky?), overclockability, potential upgrade paths. As a first time builder, I've done substantial research on parts and pricing, but a little feedback from people who have been there before would be greatly appreciated.

Is the GA-EP45-UD3P really that great? I've heard good things about MSI's offerings. Also, with regard to my PSU, it's actually $64 post-rebate.

Since it came up, I might as well post rebate prices:

OCZ RAM: $37.50 after rebate
PSU: $65 after rebate
Graphics: $85 after rebate
Motherboard: $175 after rebate (figure in the ~$50 price point for the cooler and it's mostly a wash, price-wise)

As far as Vista Home Premium 64, that's a great point. I was initially thinking 64, but I've seen so many system builds (including Tom's Hardware) that used 32-bit Vista, I assumed that it might be due to a performance difference, or that there still might be lingering compatibility issues with certain games (I still use XP Pro as my primary OS, so my Vista gaming experience is limited.).

Use Vista 64-bit. Personally I would think about getting a E7300 and overclocking instead in order to afford a Radeon 4850. Otherwise good job.

Thanks for the feedback!

I ended up buying all my components on Newegg and did the 64 for 32 swap that everyone recommended. (and picked up another 4 GB OCZ reaper RAM)

As for the motherboard, I've decided to stick with the MSI P45 Platinum based upon some reviews suggesting that it is capable of reaching exceptional FSBs.