Ratio of game cameras to hunter is the same as hunter to the time to check those cameras...ha.
I put out a couple cams to make sure the herd is in my spot around august. I check them week before the season to make sure traffic is coming through. I've found that locating a herd any time before August really makes no sense cause they are unlikely to be there come rutting season. (unless you're into absent photography)
currently i only run 2 because that is all i have. i use them more just to check to see whats going on in my area. not really for trophy evaluation, more or less just to see whats hanging out.
Thanks to Camofire I pick up a couple cameras a year and never spend more than $65 on a camera. I only need a trail camera to be nice enough to take a picture and for me to tell what the animal is (6x6 elk, 4x4 deer, 2 point etc) I don't need 16 Megapixel cameras with built in screens and all of that.
This year I put out 5-6 cameras, next year will be 8-10 if I draw my LE Elk tag here in Utah.
I have been running three to four this year. Finding it is hard to check all cams in one day. some are couple miles apart. Course I have all my cams in one general area. Need to start branching out more. But of course it takes time which can be limited at times.
I have 9. I cover 3 to 5 hunting units a year so I need lots. I use re-chargeable batteries from Amazon (EBL 16 Pack AA 2800mAh Ni-MH). I also have a rapid charger I used in my car (Energizer Recharge Rapid Charger) that I use to charge batteries between locations. The batteries are a little pricey but they save you in the long run.
8 camera. 4 in my elk unit and 4 in my deer unit, each set about 4-5 weeks before season running through the season (for elk) and the deer cams stay out until February (prairie plans unit - need more home range data).