Mine always starts off in my Lowepro Slingshot, but then as soon as I get where I'm going, it stays around my neck either just hanging or sometimes with one arm through the strap so the camera sits to one side. The 18-200mm can creep, which can be a pain, but with smaller lenses like my 10-20mm it's just fine.
I took someone's advice when I bought my camera and immediately replaced the strap with an Op/Tech USA strap and that is just invaluable!
I think travelling as much as I do and carrying the camera the way I do makes me not as eager as I would normally be in upgrading bodies because the size and weight of the D80 even with the 18-200mm VR lens is comfortable enough to carry around your neck all day on hikes without it dragging you down. It would be nice to be able to try out a D300 for a day though to see if the extra weight makes that much difference