I already have the AF-S DX NIKKOR 18-200mm. I like that one a lot. I really need a good dedcated macro lens and I did get a Tamron but I'm not too impressed with it really.
The new 28-300 is Nikon's answer to your lens but for the FX format. I read lots more about it yesterday and I can't fine one bad review anywhere and no lukewarm ones either so it looks like I'll get it.
I had been wanting the 24-70 F-2.8 but for the same amount I can get the 28-300 and the 50 1.8 for use in low light. Since I don't shoot that much low light and the fact that the D700 has phenomenal high ISO quality, I don't think the extra few stops the 24-70 has will be missed.
I've tried quite a few third party lenses over the years and have never been 100% satisfied with them. Nikon makes the best glass for Nikon, Canon makes the best lenses for Canon, etc.