The boarded up areas in World Showcase are just areas where there were shows and displays for the Epcot Food and Wine Festival, which just ended. I believe they are just in the process of taking everything down and replacing the areas with sod. The wall in the MK around Ariels Grotto is the area where 20,000 leauges used to be. They are redoing that area, and for the time being, they are going to make that section a character greeting area, and it will be connected to Mickeys Toontown Fair in the back. Rumors say there may be something else going in there in the future, but there are a lot of rumors about that spot.....stay tuned.