Will this bottleneck?

Hardware Hub CPU
1

will a core i5 3570K bottleneck GPU?

2

It all depends what your doing but it should be fine with any single graphics card.

3

And double SLI, and triple SLI (using 8x/8x/8x) (also crossfire, just force of habbit). It has lots of power, no current GPU could bottleneck it.

4

Dual 670 or 7950? (future upgrade)

single card for now

5

It wont.

6

Even 7950 crossfire?

7

Nope