For me, no—not at the moment. I recently returned from a week and a half of photography in the Rocky Mountain parks, with the D700 being the primary camera when on the move in the vehicle and the X-Pro1 when on foot around town. The D700 is big, heavy and loud, but with the 14-24mm and 28-300mm lenses capable of capturing whatever is waiting 'round the bend. In fact, Fujifilm has a line-up of lenses either imminent or on the ground that would do the job.
The one thing the Fujis lack, which guarantees a place for the Nikon, is its GP-1 accessory. When shooting in unfamiliar territory, every shot has the coordinates and altitude embedded in the EXIF data. Open the folder in a number of applications, and I can see exactly where the exposure was made. If Fuji were to include a GPS, or even a convenient input for a GPS, I might consider abandoning the D700. For day-to-day shooting, the X-Pro1 does all the heavy lifting. When I have absolutely nothing in mind to shoot, the little X100 is in my pocket or pouch.
All three are capable of excellent image quality, and closely match the way I shot film for many decades. While I had a variety of special purpose cameras to solve specific recurring challenges, a 35mm and medium format SLR did the bulk of the work. For personal work, street, etc., it was the Leica and medium format rangefinder/viewfinder cameras. After work, a compact rangefinder, predominantly a Konica S3. The combination served very well with film, and these three come pretty close in digital.
I was literally seconds off pulling the trigger on a xpro with 14mm lens but then I hesitated. I do feel comfortable with my 1ds .... But.... Have thought about replacing the 550d, therefore I ordered the x100s 
