if you know what you are doing. if you are good photographer. if you have short budget. this if camera for you. d200 has everything you need, but fullframe matrix...
I was used to film SLR's (Nikon F) and compact digitals (Nikon Coolpix 5000 and 8700), and I bought the D200 in order to use my old Nikkor lenses. I was really impressed: it has a film quality with it that's wonderful, especially with some good lenses (I prefer the 55 f/3.5 Micro-Nikkor above all); and the ease of use and completeness of commands is a pleasure-nothing to do with the unfriendly mess of compacts. You feel in your hand how well it's built, although you pay a price:weight; not too much, but surely more than a D40. The more I use it the more I think it can be the ultimate digital camera (who needs more Mpixels, or better colour control?): if you use lesser lenses the camera will give you lesser results; with good lenses you have wonderful results-both onscreen and in print. (And sorry, I don't think the new plastic zooms like the 18-55 are good enough for it). I use to shot Raw and then use Photoshop with Camera Raw, but it's quite good also with JPEG (better fine)-and this way I don't miss the quality of film. The only thing less than perfect is White balance under artificial light: you have to set it by hand since the auto mode doesn't work well. The only thing I wouldn't do with it are large landscapes (I still use my Linhof 6x9), but I didn't give it a fair try yet...maybe it'll be a surprise also there. In any case if you want a deeper review just go to the specialized places: I find the most useful are Bjørn Rørslett (www.naturfotograf.com), Ken Rockwell and DpReview.