For me, it's all about size of the scope being matched to the gun. On long range guns that already weigh 12+ pounds, a big scope with lots of magnification is right at home. If I plan to be shooting past 300yds on a regular basis, I'll take all the mabnification I can get. But on a slim little Contender carbine, a 6-24x scope just ruins the balance for me. I had a 223 that I kept a 6x scope on just to keep the rifle as compact as possible.
For my "walk about" rifles that I carry while walking in the woods, no necesarily hunting big game, I like fixed 4x or 6x scopes. They help keep the gun nice and light and easy to hand carry without a sling. On a big game rifle, I'm moving to 2-7x or 2.5-8x range scopes on my rifles. I've found that 7-8x is enough for me to make reliable hits out to 300yds from field positions, on an 8" gong. That's good enough for me. If I plan on taking shots beyond 300yds, I'll take one of the heavier rifles with a bit more magnification on there.
More than anything I think it has a lot to do with where you live, like others have said. I spend a lot of time in thick cover where high magnification will cost you an animal.
Andrew