I use both a Nikon D90 and a D50. I consider that Nikon cameras offer better ergonomics, more photo-oriented than gadget-oriented cameras. They shine in low-light, are very well made, though and don’t care as much for video. I want a photo camera, not a video camera. If I want one, I buy one. This statement is both biased and personal, just like the rest of the text :-)
My Nikkor lenses: 20mm f/2.8D, 35mm f/2D, 50 f/1.8D, 55-200 f/4-5.6 DX VR
I consider fixed focal to be a plus for creativity. Zooms are useful for money-earning photographers, for their contracts. With a fixed focal length, one moves and pays attention to his framing, a lot more than he would with a zoom. One is also more discrete and lighter. Think about it, a 969g and 13cm long 14-24mm 2.8, or a 270g and 4.3 cm 20mm 2.8? A 900g for 13cm 24-70mm 2.8, or a 155g for 4cm 50mm 1.8, which is also faster? Good zooms are a work tool for pros (weddings, events, etc.), fixed focal are creation tools, because they restrict you, you have to think!
Those who have only experienced reflex photography with zoom lenses should hang around with rangefinder users, you’ll understand really fast.
Take nice pictures!