You would be more 'future-proof' with the P35 board. You won't be able to o/c much at all. Therefore, the 965 boards are better for o/c. Since DDR3 isn't a viable choice for a year, memory is OK, just recheck the Voltage ratings and go with the lowest. The P35 board WILL boot the memory at 1.8Volts, and WILL NOT auto-detect. Red-letter warnings about this at Intel site. Look for a 1.8-1.9V memory kit if you go with the P35. Consider G.Skill if availible. Most 965's auto-detect, but some DO NOT. In general, stick with memory having Voltage UNDER 2.00Volts. IMHO, you might re-evaluate yor choices to see if this criteria is met.
'Future-Proof' of the P35 boards means Quads, and 45nm CPU's, consider that alternative for the next year, as these CPU's (especially the 65nm Quads) will get cheap fast. Later this month on the 22nd, Intel will cut the Q6600 price IN HALF! (about US$270), making it only $40 more than an E6600. Many gamers will go to the Q6600 at that new price. (NO BRAINER)