All good ideas, Lowebow has a very good idea if your hunting from a tree stand, or still hunting on the ground, a little insulation goes a long way. If you use antiperspirant on your feet, your body will perspire more someplace else. The problem with the hand/foot warmers is that once in the shoe, they don't get as much air and start shutting down, at least that has been my experience. I have never used a pair of battery socks but have heard good things about them.
I use mickey mouse boots, and I installed zippers on them which makes it real easy to remove and put back on. When I get to my stand, I take the boots off for a minute or two and let the moister escape.