I made the switch a couple months ago and its harder than you think. There is a lot of convenience you take for granted in the smartphone age.
I also refused to get a mobile phone for years, much to the chagrin of my girlfriend(s). It meant I used to come home to an answering machine full of messages and feel much more loved than I ever have with the immediate drip feed of messages I get now.
I wonder, what will I really miss that a book and a dumbphone won't be able to replace in my life? Perhaps the maps.