Mojang today released more information on PC Gamer about the map item that will be released on the minecraft 1.6 update.
“Maps will start out as a blank parchment and you will need to have it in your hand and move around for it to be filled in. You will also be able to copy maps from your friends to save yourself from the back breaking work of filling it in. Nifty, huh? Apart from maps, 1.6 will contain a huge bunch of bug fixes to make the game more stable.”