D200 is slightly larger and significantly heavier than my 3 year old D100. The magnesium alloy body which contributes to the 900gr+ weight makes it a lot sturdier then the high impact plastic of the D100.
Contrary to most people, I like my cameras heavy; the more weight the better. It gives you a very stable experience. It also balances great with my lenses. The combined weight of the D200 with my 17-55mm lens is in excess of 1,5 kilos. Don't be afraid someone will try to steal it: you can always beat your assailant to a bloody pulp with it.
This one is a no-brainer. They took everything that was less then easy on the D100, and fixed it. All main settings can be configured without having to go through menus. I click the ISO button, dial the value, done. Different white balance? easy. You don't even have to move your eye away from the viewfinder.
Besides these improvements, Nikon continues to uphold their reputation in interface design and ergonomy. Everything is in reach, and I never had to glance at the manual to find out how something works. A triumph of usability if you asked me.
The TFT-screen on the back of the camera is massive. I'm not much of a chimper, but the high resolution and contrast really helps you determine if your shot was in focus, or adjust camera settings. It's about twice as big as the one on the D100.
Everything on this camera is fast compared to the D100. Power up-time (which already was really fast on the D100), Write speed, mirror blackout, autofocus, software behaviour. And lets not forget the 5 frames per second machine gun mode. Must be frightening from the other end!
I'm looking forward to using the camera on my upcoming vacation in Norway, allowing me some time to really get acquainted with the monster.
The kit isn't complete yet. I also ordered the optional battery grip, but It hasn't arrived yet. It's probably en route to the Netherlands, but arrival date could be anyone's guess. Another thing I hadn't ordered yet was a dedicated flash unit. I had decided to first try my current SB80-dx, but unfortunately ran into some problems with automatic settings. So I'll be looking to invest in a SB800 after I get back from Norway. I don't need either whilst in Norway, so no worries there.
Ahh.. the toys that keep the geek happy ;-)