I can't see why anyone would opt for the D800 over the D600 unless:
1. You need 36 MP for some specialty purpose, like testing lenses, making wall-size prints, or scientific photography. A few months ago, 24MP was the gold standard in resolution, and most pros were quite happy with their 16MP D4's and 12MP D700's.
2. You absolutely have to have the "pro" control layout, either because you are regularly switching between the D4/D700 and this camera, or because you're a body snob. My guess is that if the D600 had the "pro" controls, B&H and Adorama's websites and phone lines would be overloaded with people canceling their D800 orders.
3. You think you need the 51 point AF of the D800. The only scenario I can see where this might be true is if you are a professional action or sports photographer. And, if you are, then you are/should probably be using a D3/D4.
24 MP is a HUGE amount of resolution. When I stepped up from my 12MP D90 to the 16MP D7000, it took me months to adjust my technique (and replace some slow focusing lenses) to the higher resolution (and it's correspondingly higher revelation of poor focus and technique). As for controls, the D7000 controls (which the D600 matches almost exactly) are very intuitive. Since you aren't already wedded to the Nikon F6/D4 controls, you won't miss them. There are pros on the Sports Forum who have shot sports with the 39 point AF system, and the results are great. For things that don't move (and even things that do) the D7000/D600 39 point AF is just fine.
In summary, I recommend the D600. More good news: there are a ton of good FX/Film lenses out there for you to consider. If it were me, buying my first Nikon DSLR, I'd get an AFS 50mm f1.8 prime and take my time deciding on which mid-range zoom is best for my type and style of photography.