I was leafing through my guide book and tripadvisor last night trying to put together an idea of what I might do whislt I was in Seoul. Also spotted this on the points guy blog which might be of use:
Seoul Guide
FWIW, my rough itinerary is
Friday afternoon - North Seoul Tower (Namsan), War Memorial, Food Tour 6pm
Saturday - DMZ tour, meal at 8pm
Sunday - possibly follow the suggested plan in the what to do section of the points guy guide so Gyeongbokgong Palace, ToSok Chon lunch, Chenggyeong Palace, Biwon Secret Garden tour (English tour at 3.30pm), Insadong, dinner somewhere, Cheongyecheon stream walk
I would also like to go to the fish market at some point - perhaps Friday afternoon or Sunday morning, and to visit the Battered Sole restaurant which was recommended on the main Seoul thread. Also the Bukchon Hanok Village looks interesting although I am probably struggling to cram this in somewhere.
Anyway, thought it may be of use to put this up. I am also waiting to see if there was anything that has come up as a must-do from last weekend.