Right now, I would get the i7-2600k (~$330). The 2500k is also possible. They have a different built-in GPU, but that doesn't matter to me. Both seem to easily hit at least 4.5GHz. The ASUS P8P67 Deluxe is my choice for MB. You could get the P8P67 PRO for less and some missing features. I will at least wait for the Z68 MBs to come out. To be able to use the graphics and overclock at the same time could be handy.
It always comes down to what the computer is going to be used for.
_________________________
Never argue with an idiot. They drag you down to their level and then beat you with experience.