I've checked the daily pop throughout the past few weeks and found pictures that seem to take place in a city. Check them out:
Did you notice the 3rd to last picture (Berry Delicious), nice pun Poptoropica.
Also the last picture is of the Wok and a Hard Place (Restaraunt), based of the saying "Rock and a Hard Place"
I hope the Poptropica Creators' announce this island soon.