How is this build?

Hello all. Ive been doing some research and I am looking at building myself a little powerhouse. Im trying to keep it somewhat resonable (srry no 945 in my bank account) but still be ready for whatever I throw at it. Heres my proposed build, ive changed a bunch of times, but I think this setup works the best for me.

Currently I have a Thermal Take Armor Full Tower ATX case (great buy at compusa) so I have space for everything plus some, and a Corsair 750TX PSU.

Im looking at getting:

CPU = AMD Phenom II 720 BE
RAM = ???
Video = ASUS EAH4870 DK TOP/HTDI/512MD5 Radeon HD 4870 512MB 256-bit GDDR5 - Video Card

Heres where I have a problem. Newegg currently has a great deal on the Phenom II 720 BE AM3 mated to a ASUS M4A79 Deluxe AM2+/AM2 AMD 790FX ATX AMD Motherboard. CPU MoBo Combo

Is this better?? Asus AM3 MoBo

Or this??
http://www.newegg.com/Product/Produc...82E16813131366

I noticed that the AM2+ can only support DDR2 ram as opposed to the AM3 with DDR3. Is it that big of a difference between 1066 and 1600??

That is the 'proposed' build not including HDD and DVD drives. Im planing on using stock CPU cooler for a time until I feel comfortable to OC the CPU.
The deal is that I can get everything here for 530, so it seems to be a good buy.

Thanks in advance guys!!!

BTW: Killer deal on the video card, you can get it for 154!!!