On-trail, the camera is around my neck, usually over one shoulder but over my pack straps so I can access it quickly. Usually the 24~120 zoom on the camera and the 12~24mm wide zoom in a padded pouch on the waist belt of my pack.
Off-trail, it depends...maybe in my pack if I'm climbing steep enough stuff that it would get banged around on rocks or still slung the same way on top of my daypack straps.
I know some folks who use various brands of hitches that hold the camera against their chest but allow them to pull it up to eye level. Have never tried one of those but the guys who use 'em swear by 'em.
I haven't used any sort of "never-ready" camera case since I stopped carrying my old Nikon FTn film camera and then just the bottom half of the case because on the '70s era Nikons, you actually removed the back of the camera to load film so you needed a spot to put the loose piece while you were switching film. (Nikon used to call them "ever-ready" cases but most of us left the top/front half of the case at home because if you had to open the case, you were "never ready" to take a quick shot.)
You should have seen some of the looks I got in the middle of a 100-mile trek out at Philmont with the D200 around my neck. The question was usually something like, "You're carrying THAT out HERE???" To which my response was, "Yup. This is my lighweight backpacking camera. You have a problem with that?" Which wasn't that far off...my NON-lightweight backpacking camera is a Mamiya RB67 2-1/4x2-3/4 (film) camera. Now, that is a boat anchor...
For short day hikes from the car, I may carry my camera/computer backpack. It's similar to
this one but made by Targus and I can't seem to find the exact model right now. The top is just a pack area but the bottom with the flap lid has dividers and will hold the D200 with 24~120 plus three or four more lenses. The laptop sleeve is against your back and runs the length of the pack. The one I have does have a (non-padded) waist belt so it is quite tolerable as a daypack. I can carry the D200, 24~120, 70~210, 10.5 fisheye and 60mm macro if I want a full range of capabilities. It will still fit in the overhead on most aircraft except the Embraer "sardine cans." On those, I have to take the laptop out and put it under my seat and then the pack with camera gear will fit.
I know there is a lot of debate about cameras but having the larger image sensor (size, not megapixels) and better glass in front of it makes the extra effort of schlepping the D200 well worth it.