This image is bound to make many of you very happy.
Minecraft designer Markus "Notch" Persson released it earlier today, along with this tweet: "Any resemblance to anything at all is coincidental." Well, that's reassuring.
Thankfully, he provided more detail in a blog post on mapping. Maps are of specific areas, so the location where you craft one will serve as the center of that individual map. This functionality will be integrated into multiplayer as well, in case you were wondering. Talk about a godsend.