Back in the day you bought the best camera you could afford with the idea that you could hand it down to your grandchildren. And it would be great working condition and perfectly usable. Now, a digital camera has a functional lifespan of around five years. Sure, they still work fine but they're obsolete in terms of technology.
I have two Nikon D2x cameras. That's around $10,000 worth of camera and they sit in a desk getting dusty because newer cameras that cost far less money have far greater functionality.
If you're a photojournalist or sports photographer, where high frame rate and a big image buffer is important, then fine, the pro level cameras are necessary. But for all other folks, including pros like me that work in a controlled environment all of the time, the camera body is no longer all that important. Get the good, middle of the pack camera body. 16 mexapixels is plenty, 24 is more than enough. 36 megapixels is stupid unless you're shooting for billboards. My clients hate 36 megapixel files and barely tolerate 24 megapixel files.
Put your real money in to lenses. That's where it really counts.
High megapixel cameras are not forgiving of lesser lenses. Your lenses will transfer to newer cameras down the road. Top notch lenses do not become obsolete.