Nikon D600 Raw can be opened with Gimp 2.6
I just got D600 and took a few pictures. I transferred raw .nef files to my HD using View NX 2. Gimp 2.6 that i use occasionally was able to open all my .nef files. I am debating which one to get: LR4 and Aperture, and since Aperture does not support D600 raw, I am leaning toward LR4. I am also pleasantly surprised by usability of View NX 2. Both Gimp and NX 2 are free. I will probably wait for Aperture update or 4.0 and then make my decision.