I'm kind of hardware guy so I'll just put my thought here :
CPU : If I were you, I would choose sandy bridge's i3 (price are the same, around 130), the main reason was the power consumption, temperature and general performance. Phenom are quad-core, and believe me, many application still unfriendly with multi-cores, resulting the potential hidden in quad cores wasted on those application, for example RMXP lol. More cores are supported and optimized for design application such as 3d, architecture and movie editing software.
GPU: Well this is subjective, I'm no AMD fanboy but If I were you, I invest in AMD 7870 for better price/performance. Not to mention AMD has better multi-gpu support for future upgrade. In the other hand, NV has PhysX, which in several games, can boost the game visual (subjective). PhysX is emulated if not using NV cards, but requires far more processing power = lag. To take a note here, If you're running any games in 1440x900 and below using $250++ cards, you're just wasting your money and power.
M/B : No comment here. M/B are just for features, brand, and color. The truth is, I buy M/B for the looks. Of course not just looks. I have to make sure it support future upgrade, current technology trend and have god support and price.
RAM : Maybe you should buy faster 4GB ram (more frequency and less latency) which will bring better performance, your board support up to 2k hz. If you're not doing serious photo/movie editing, big database import/export, 3d rendering, i guarantee (for now) that 4GB would suffice, even for latest game with highest texture quality (non-MOD). I MOD my skyrim using insane texture and seem that my 4GB memory not suffice. Else than performance issue, just like M/B, design and colors matters (at least for me)
PSU : GTX570 with phenom should be around 500-550 full load. 700watt are.. hmm, not a perfect choice if in the future you're going SLI. if not, then its just enough. You should be buying Seasonic M12II-620 (modular or not up to you) which has better quality than that.
HDD : HDD less than 1TB are gimmick, why ? the price between 350 vs 500 and 500 vs 1TB are very small. If you want performance, go SSD. Do your computer runs on long term non-stop ? if so and you like to store many tihngs, go for WD RED, yes, WD red the NAS edition. Ok, if you don't have money to buy SSD and you want fast HDD, then considering buying samsung F4 or WD black, though for me personally, those are gimmick (high price with slightly better performance than standard HDD. Not to mention their lower durability and higher temperature). NEVER touch 15k/10k rpm wd raptor, those are utter gimmick even though some people report those in RAID provide competitive against SSD.
SSD : No No No ! I don't recommend you use any SSD else than : Intel 330/520 (120GB and higher, 60GB has slower performance), Crucial m4, and Samsung 830. Reason ? Speed, durability, and support.
CASE : up to you, I recommend those with bottom PSU location, space in the back for cabling support, USB3, and positive pressure cooling air flow
ODD : no comment, I rarely used my optical drive. But hey, Blu-ray drives are getting cheaper and it'd be wise if you invest in that, for maybe in the future you need to read from blu ray
btw, hyper212 was a great choice

and, if you think your ultra setting skyrim was beautiful, try this :
http://skyrim.nexusmods.com/mods/11. I did and the result... well you'll see when you try it.
Hope it helps
--- EDIT ---Don't forget to turn off
win7 auto defrag if you're using SSD as main drive (newer windows update should do this automatically if it detect the main drive as SSD, just to make sure). SSD could suffer from durability by defrag, its lifetime determined by how many data were re-written inside each block in SSD. Defrag is useless in SSD as it using different data-read-method compared to HDD. HDD seek the data in specific location in the platter, the data are frequently changing places and defrag was used to re-align those data so "seek" process become faster. While in SSD works like RAM, call the data based on addresses so its absolutely no need to defrag. Use drive monitoring application such as HDTune to check the condition of your SSD