10/23 Price List
It looks like the available chips for the Socket 939 will be:
Athlon64 X2-4600+ $224
Athlon64 X2-4200+ $175
Athlon64 X2-3800+ $149
Athlon64 3800+ $109
Athlon64 3500+ $89
Sempron 3400+ $69
Sempron 3000+ $54
Sempron 2800+ $51
I think the X2-4600+ is about even with the Athlon64 3800+ in games that aren't optimized for dual cores.