(This post is from an email conversation with a coworker. I thought the content might be useful for others.)

Q:  I know you mentioned that you were not using your D800 much due to file size, so I am curious what you think about what you have read on the D600 to date.  Due to work consuming a ton of time I have probably not taken 200 pictures with my D800, and since I do not see this changing anytime soon, I need to rethink how many cameras I need at this point so any thoughts would be appreciated.

A:  Are you considering replacing the D800 or augmenting it?

I’ve realized that I probably will keep my D700 for the reason you mention.  For family pictures around the house, the D700 is completely adequate and gives me 1/3 or less data to mess with, but still with great quality images.  Do you still have your D3?  Of course it’s faster, but otherwise similar file sizes, etc., to the D700.  Though I don’t love 50MB files, I do love knowing I’m sucking every bit of detail possible out of a scene, so I like the D800 where appropriate, and then use the D700 for other pics where I don’t need/want all the detail.

I’m going to get rid of my D300 whenever I have time.  At some point I’d like to replace my D200 IR body with a D700 converted to IR.  That would make me full frame across the board, and would allow me to get rid of a number of lenses.

I think the D600 is fine, but there’s not a whole lot of difference between 24MP and 36.  It would be nice to have a bit smaller body, and it does give you a slightly faster frame rate.  Otherwise, its interface isn’t quite as configurable button-wise, so I’m not sure I’d love it like I do the D800 and D700.

If you’re wanting to back down from leading edge capabilities, then a D600 would be a good general-purpose full-frame body.  Is that the direction you’re considering?