Lensmate sells a "solution" to this - I bought one - along with their thumbrest for my newly-acquired X100 - before the camera arrived. After a few days using the menus, I don't mind the OK button's responsiveness so I haven't added this sticky accessory yet. Maybe after a few days of real world use, I'll see if I really need it. I've tried to set up the camera so I won't have to use the menus very often when I'm shooting anyway, we'll see how that goes.
Terrific forum you have here!
The lensmate "OK button solution"
Lensmate: Lensmate Fujifilm X100/X10 Menu Button Solution