1) Not sure which motherboard to get. I think I want the asus p8p67 Ultra. I was thinking about the p8p67 Sabertooth (I like the shroud).
I think either of those will be okay, but hard to say without so many reviews online.
2) 1333 DDR3 vs 1600. No difference on Sandy Bridge right?
The bus speed is basically locked at 100-105Mhz, so I believe most of the boards will operate a memory multiplier, so in theory with support for faster DIMM's you will get more bandwidth if you run 1600 RAM. Again, my knowledge on this cutting edge hardware is limited, but I believe what I say to be true.
3) Does it make more sense to get 2x 6970's over 2x 6950's? I don't want to void warranty by flashing the 6950's in case I sell it in future so I can upgrade quicker down the line.
Both cards have dual BIOS's so if you flash the 6950's to 6970's to revert back you simply flick a switch to use the original bios to boot from, then flick the switch back, and can flash the first bios back to the default, although that won't be possible with a dead card. IMO it is worth the risk, as the number of hardware items I have had fail have been very few, apart from PSU's when I first built my first PC, although I bought the cheapest shit I could, not knowing any better.
4) I need a white case, that's why I chose the phantom.
Corsair 600T White? Spray paint? ;)
5) What's best modular PSU between 1000w-1200w that will last me a couple builds but not break my bank?
I am not sure you would need something so high powered, but the Antec 1200w High Current (believe this is modular??) or the Corsair AX1200 would be top of the line. Futher down the line, I believe seasonic are coming with a X-1000 model, that should also be good, if/ when it arrives. For slightly cheaper alternatives I think you could do a lot worse than get a 1000w HX Corsair, if you really want a PSU of that rating.
6) NEW SSD's announced at CES. Should I wait until those new SSD's come out before buying current ones?
Yes IMO you should, although the performance of the current sandforce (Vertex 2, Force etc) is fantastic. I haven't bought one because my old P35 board will not get the best of them, and I have other things in dire need of replacement first.
7) Caviar Black best HDD to buy for now?
Maybe... The samsung F3 1TB is also good, and fast. If you want to add an SSD later, maybe get a larger HDD of a more eco- orientation? The F4 EG (2TB, 32MB cache and 5400 RPM) runs circles around my Raptor, I get at least 110MB/ sec on the inner tracks, and it is basically silent. Very impressive.
8) Planning on overclocking CPU to 4.6GHZ with stock heatsink (many reviews said you can get easy overclock on the new SB processors with stock heatsink). [h] review said this too.
I would always upgrade the heatsink to something a little more capable, although the stock heatsink should be fine!