I'd go with a P45 based board myself, oh wait, i did. I've been gravitating towards Asus products lately, the P5Q-E would be my suggestion. The only advantages X48 seems to have is the 2 full speed PCI-E slots and official 1600FSB support. However the P45 can use more ram and more importantly the cheaper DDR2.
Intel Product Comparison Chart
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|Q6600 at 3.0|Diamond HD4870X2|G.SKILL PC2-6400-2x2048|P5Q Deluxe(0803)|1.866TB|XFiXM|245B|AL1916W|
Folding? If you're not doing it, you should ask about how to.