Straycat, used one for two years professionally; great piece of kit that I had not one problem with. only upgraded to a D2X for the built-in grip and slightly better weatherproofing.
As far as useable ISOs go, never had a problem shooting at ISO 1000, providing I got exposure nailed within 1/3rd stop of perfect; go either side of that and then you run the risk of bringing out too much noise with processing. Still, for A4 prints ISO 1000 was fine.
I shot a lot at ISO400 and 640 without any doubts over quality. Okay, compared to the D300/300s and the high-end, newer Nikons then the technology has moved on a lot but considering mint D200s are shifting for £400-£450 these days, they're a bargain.
FPS is good, battery life is okay (better with a grip and two batteries fitted) and handling is second to none. The menu system is brilliant, the controls are infinitely better than the competition (namely the 30D and 40D, which i used at work) and AF is good with both AF-S and AF-D lenses. Metering on mine was just about spot-on, although i mainly shot in manual.
I generally shot JPEG, which were fine - plenty of detail - although I did find that the raw files it produced were very flexible if you wanted to put in a bit of time on the computer. I won't say they're better or worse than the competition; it just produces great results.
As a workhorse camera for everyday shooting it's a great buy. For large prints you're probably asking too much for A1+ resizing but for A3+ it's more than capable.