Actually I wouldn't want a dual socket C2D setup for the same reason I don't want a 4x4, 2 CPU's = 2x the heat, 2x the heatsinks, 2x the power draw (speaking to CPU requirements only), but is it 2x the performance? I think not. I am of the liquid/TEC cooling variety, and a dual processor setup just creates way more headaches than it is worth, imo.
I think it that dual processor systems were a good idea 5 years ago when CPU 's weren't all that fast, but now that companies can get more than 1 core on a given piece of silicon the dual processor setup isn't as useful.
We see companies touting the ability to game, encode, and virus scan all at the same time, but in reality what they are saying is "our code isn't entirely optimized for multi-core architecture so we are telling you do do 100 things at once in order to justify your purchase."
You are looking forward to 8 cores, fine. However, what benefit is derived if the software is still lagging behind and working on dual core support? I would suspect that 4x4 will be an improvement, obviously, but also that AMD spent too much time on it and not enough time on improving its architecture.
I honestly don't believe 4x4 will be AMD's saving grace, but it will make for a cool marketing stunt just like quad-sli.