Yeah, that was a big part of buying the D200. I have a D70 and shoot mostly outside at events where there is usually more than enough dust being blown around to make me nervous about changing lenses out in the open.
The D200 was on sale, so it wasn't all that much more than buying a D80.
I'm a bit disappointed that the D70 batteries won't work in the D200 though. But the D200 batteries will work in the D70 apparently, so maybe Ill just get a couple more of those so I only have to carry one kind of battery around.
I also popped for an 8GB Compact Flash memory card, so taken all together, there goes my lunch money for the month.