I'd pick a Samsung F3 over any other every day of the week. The F3 is the fastest and one of the most reliable drives out there. Plus, Seagate's gone a bit south in the last few years. Spend the extra $10-15 on a better drive.
This RAM is identical to the RAM Why_Me linked, except it's a different series (different heatsinks). It's got a promo code so it's only $60 this weekend, so you need to get this asap if you want the deal.
+1 to a better GPU. You should be looking at a 560Ti/6950 minimum for 1920x1080.
Nothing official regarding requirements for BF3 at this stage (nothing out of E3 'sighs')...
Given there's space in your budget for it... I'd go for a stronger GPU setup. Pick any of the boards posted by the experts above that support dual cards and go SLI gtx 560 of CF 6950. Either will serve you well
Get the 570. Although 2x460s OCed will most likely best it in performance, the 460s can't be upgraded any further than SLI and you'll be maxing out their usefulness by OCing them as well. Down the road, you can always drop in another 570.
IMO I'd get a 6970, because you'll be getting better performance for the same price (6970 > 570 in most games).