nice question but hard to answer if you don't give us a budget limit for the best Nikon, as the bodies can go up to over 4000$ (for the D2Xs)
As for the newest Nikon DSLR, that's easy to answer: it's the D40x, which you can find here in Gordons preview: http://www.cameralabs.com/cameras/Nikon/
The D40x seems to sold only together with a kit lens and starts at around 900$ incl the AF-S DX 18-55mm 3.5-5.6G ED II lens.
So give us some direction as to the amount of hard earned cash that you plan to part with...
Plus how "far" you'd like to reach with your telephoto lens? Have any experience so far with other cameras and their "long end"? Then you could give a hint like "I'd love to go 2 times larger than the long end of the xyz-camera/lens". The 70-300mm you talked about in the other thread is certainly some serious long/far reaching lens. Are you thinking about giving your equipment back? Still problems with your D40??
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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