that Neo2 Platinum board is what I would get too, but I want the new stuff (PCIe support). I have to see for myself the gains I can get from it.
I'm planning on getting the 3200+ Athlon 64, but will most likely overclock it. I'm going dual channel too so this should be fun to work with. By far, this will be the best system I ever had.
Did you order your stuff from Newegg? They have the fastest shipping ever!!! I get mine in two days, but it's the weekend now and they are closed. Should get it Monday. FedEx is the best.
You will definitely see a huge difference from what you are using now after you get that system built. That 2x512MB dual channel is a better choice if you get around to it.