I tried out a number of bags in the camera shop.
Got the Lowepro Flipside 300.
2 strap backpack style, with carry handle on top of the bag.
Holds the D80, 50, 60, 85, 180, sb600, 18-55 AND 55-200.
AND: I can strap on a monopod or tripod and carry that TOO!
(Yes, it's kinda heavy; no, I don't pack alllll my lenses allll the time...)
I didn't like the one-strap, over-the-shoulder bags; too unwieldy and unbalanced for me.
I could feel future neck/shoulder cramps and hear myself complaining...
A lot of my landscapes are from waaaaay up in the hills or waaaay down in a creekbed.
I liked the backpack style.
I can hike around and not worry about losing my bag or having to shift it shoulder to shoulder to get around.
I've beat on it for a couple years; it still stands straight and hasn't lost any seams.