Mickey's Birthdayland....Toontown Fair...Toontown et all was only put in as a temporary new "land" for Mickey's Birthday many many years ago. It was kept around because of it's popular appleal for just about everyone to have a chance to meet Mr. Mouse. But the infrastructure has seen better times.
Times change....and Mickey is not quite as popular as the Princesses are now. And it's not just the princesses. Dumbo is getting a whole new mini land out of the deal, a new table service restaurant, and Ariel is getting her own ride.
Have you seen the blueprints? It looks like it will be a really nice addition to the park. And dont you worry anout Mickey and Minnie, they are getting a whole new meet and great near the front of the park.