The new maps for congressional districts, state house, state senate and Chicago wards are now all official. Are you interested in seeing how the new maps overlay with the old maps, or with each other?.
Here is a little app that allows you to overlay various maps to see how they are different. You can look at the new ward, congressional, state house, or state senate boundaries and see how they compare to the old boundaries, or with each other or even with county boundaries.
You can click on any district/area/region of the map and a popup will appear to tell you what you clicked on. If both layers are loaded the popup will (should) only tell you what's on the top layer.