I've also been dealing with blisters lately, primarily on my toes. I find that wrapping the sensitive areas in moleskin, and switching away from cotton socks is really helping since they tend to retain moisture. I also changed the way I lace my shoes to reduce friction on the top of my foot. So many little things to consider...never think about it until we have to.
Please let me know what you find that helps, I appreciate all the input I can get :)