The fantastic news is that PoptropiCon Island episode 1 is formally outside for everyone! You no longer need to be a paid member to play it.
This Island features your Poptropican in the center of a giant convention about to begin ticketless. You have to find a method to get a ticket to visit the convention, and solve multiple puzzles attempting to achieve just that! Contrary to other Isles, the customizer tool plays with a big role in this Isle when problem solving, and adds a new feature that is cool to the Island.
Also, there are many references in the posters stuck to the costumes people are wearing to other Islands.
Heck, there are even some references to outside world pop culture.