I've been hunting with a 30-06 for several years. It serves me well, and I have no reason to change to the "flavor of the week" just because some hack in a gun rag says its "better". More than likely, the old '06 will be around for many years to come, naysayers be damned. No sense in looking for the latest, greatest caliber to replace it; in real-world conditions, you'll find very little difference. So, use what you have, learn to shoot it well, and put meat on the table. Your rifle will kill game just as well as any of the new fangled 6-point-whatever extra super magnums.
Having said that, I used a .243 for deer this year, and enjoyed carrying and shooting it. Yes, it was lighter and didn't kick nearly as hard. No, it will not replace the '06 as my primary deer rifle, but it will certainly be used when I hunt open fields, and definitely for coyotes this spring. There is also a 30-30 in my cabinet that comes out for deer drives; again, useful but will not replace the '06. Quite frankly, I'd rather trust my life and livelihood to the old 30-06 than chance it with any other caliber.
Mac