My feet have always been my achilles heel - pun intended. I have run a half marathon and hiked every available volcano in Guatemala - one thing is for certain, blisters come and go. Hiking on the Appalachian Trail presented new problems due to the sudden driving rains, frequent elevation changes and wet feet. My Oboz hiking boots are well broken in at this point and I'm awaiting superfeet replacement insoles as the previous ones have finally given out.
Finally, I believe I am arriving at a solution. I always pre-tape my feet now with moleskin in place on my identified hot spots. I use J & J cloth medical tape, it holds better than duct tape and I'm not stingy with it. I wear two pair of socks, one Injinji synthetic toe socks, then smartwool on top. I change the smartwools every 4-5 miles to keep my feet as dry as possible. I still experiment a little but one thing I know is that if you are blister prone, cotton will not work, more than likely.
Still experimenting, I bought a pair of Sealskinz waterproof, breathable socks and will try those over my Injinjis on a 36 mile wet hike this coming weekend. I hope they work. Wet feet are my nemesis.